TRENDS AND DETERMINANTS OF FOOD CONSUMPTION PATTERNS IN WEST AFRICA By Nathalie Mongue Me-Nsope A DISSERTATION Submitted to Michigan State University in partial fulfillment of the requirements for the degree of Agricultural, Food and Resource Economics – Doctor of Philosophy 2014 ABSTRACT TRENDS AND DETERMINANTS OF FOOD CONSUMPTION PATTERNS IN WEST AFRICA By Nathalie Mongue Me-Nsope This dissertation examines food consumption patterns in the Economic Community of West Africa States (ECOWAS). The study provides detailed information on food demand parameters, which are critical to improving policymakers’ ability to make sound food policy decisions. Chapter 2 analyzes per capita food availability data from FAO’s food balance sheet (FBS) from 1980 through 2009. It identifies major contributors to diets and documents shifts in levels and composition of food supply at the country level. The analysis reveals: 1) a trend towards greater per capita calorie supplies for most countries; 2) a diversification in the composition of food supply; 3) a cassava revolution in some Coastal Non-Sahelian countries; 4) some diet upgrading in terms of protein availability; and 5) growth in daily fat supply per capita for most countries. Chapter 3 estimates the effects of urbanization and gross domestic product per capita on starchy staples (SS) demand in Senegal, Mali and Benin using an Error-Corrected Linearized Almost Ideal Demand System. Short-run and long run-elasticities are estimated using per capita food availability data obtained from FAO’s FBS and supplementary data. Support for a statistical association between urbanization and SS demand is found only in the case of millet in Mali. The results suggest mixed evidence on the effect of relative prices on SS demand and on substitution between coarse grains and rice. Evidence also supports more expenditure-elastic demand for millet and sorghum than for rice in Senegal and Mali, contrary to conventional expectations. Aggregate-level analysis of food demand ignores the effects of the distribution of income and of differences in food supply across regions on food demand. As a result, Chapter 4 uses Mali’s 2006 household budget survey data to estimate a censored Quadratic Almost Ideal Demand System model for cereals in Mali. Cereals demand parameters are estimated by rural/ urban location and by income group. All expenditure elasticities were positive, as expected. Uncompensated own-price elasticities also support downward-sloping demand curves for all cereals. The results suggest high substitution between rice and coarse grains in both the rural and the urban areas and across income groups. Chapter 5 measures the welfare effects of cereals price shocks observed from 2008 to 2011 by means of a proportional compensating variation that allows for second-order demand responses to cereal price changes. Across all income groups and place of residence, the full effect is only slightly lower than the first-order effect. This reflects the fact that during this period all cereals prices were rising sharply, limiting the scope for substitution to “cheaper” cereals. Without considering the possibility of producer supply response in the rural areas, the magnitude of the welfare loss was higher for rural households than urban households. In both the rural and the urban areas, the welfare loss from observed price changes, in terms of relative share of income affected, was greater for poorer households than richer households from 2008 to 2011. However, the absolute income loss was greater for the higher income groups. The findings present a scope to encourage ongoing diversification of staple food sources to give consumers more opportunity for substitution and choice. Price transmission across cereals suggests a need for a cereals policy rather than just, for example, a rice policy. The results suggest strong future growth in demand (pressure on prices if supply is not increased), and a need to focus on driving down unit costs throughout the food system. To My God who makes all things possible! Unless the Lord builds the house, They labor in vain who build it; Unless the Lord guards the city, The watchman stays awake in vain. (Psalms 127:1) iv ACKNOWLEDGMENTS I am greatly indebted to my major professor and dissertation supervisor, Dr. John Staatz, for his guidance and encouragement during this dissertation process. I also wish to express my gratitude to my other committee members, Dr. Robert Myers, Dr. Songqing Jin, and Dr. Kimberly Chung for their useful feedback. I acknowledge the work of FAO for making available to researchers the FBS data upon which a part of this dissertation is based. Many thanks to Dr. Nango Dembele and Dr. Boubacar Diallo for moral and academic support. Enormous thanks to Maurice Taondyandé (IITA/RESAKSS) who provided the household budget survey used in this research, and was willing to respond to data queries. My gratitude to Steve Longabaugh for encouraging me and for generating the map used in this research. I am grateful for financial support received from the Syngenta Foundation for Sustainable Agriculture through the Strengthening Regional Agricultural Integration project with MSU, under which this research took place. I also would like to thank the following AFRE faculty who supported and encouraged me throughout my stay at MSU: Drs. Scott Swinton, Roy Black, Eric Crawford, Valerie Kelly, Colletta Moser, Cynthia Donovan and Veronique Theriault. Special thanks to Debbie Conway for moral support and for always making things easier. A special thanks to my colleagues and friends, Ramziath Adjao, Helder Zavale, Berthe Abdrahamane, Milu Muyanga, Jordan Chamberlin, Mukumbi Kudzai, and Vivek Pandey, who were always available to share their knowledge and expertise, and whose friendship was a source of strength throughout this process. Heartfelt thanks to my son, Karsten for cheering me along the way; to my mom–for all the sacrifices of love; and to my siblings, nieces and nephew. I thank my A/G church family and childhood friends for the love and prayers. Many thanks to Patricia Johannes for editing and formatting this work. v TABLE OF CONTENTS LIST OF TABLES ....................................................................................................................... ix LIST OF FIGURES .....................................................................................................................xv KEY TO ABBREVIATIONS...................................................................................................xvii CHAPTER 1. INTRODUCTION ................................................................................................1 1.1. Issue and Background ......................................................................................................1 1.2. Problem Statement ...........................................................................................................4 1.3. Research Objectives .........................................................................................................7 1.4. Literature Review and Research Gap ............................................................................7 1.5. Research Contributions .................................................................................................10 CHAPTER 2. TRENDS IN PER CAPITA FOOD AVAILABILITY IN WEST AFRICA .14 2.1. Introduction ....................................................................................................................14 2.2. Objectives and Hypotheses ............................................................................................14 2.3. Data and Reliability of Food Balance Sheet Consumption Estimates .......................15 2.4. Methodological Approach .............................................................................................20 2.5. Findings ...........................................................................................................................21 2.5.1. Determinants of Food Consumption Patterns ...................................................21 2.5.1.1. Population ...............................................................................................21 2.5.1.2. Urbanization ...........................................................................................23 2.5.1.3. Economic Growth ...................................................................................24 2.5.2. Trends in Per Capita Food Availability .............................................................25 2.5.2.1. Trends in Daily Food Energy Availability (kcal/capita).....................25 2.5.2.2. Trends in the Composition of Per Capita Food Availability by Major Food Group.................................................................................30 2.5.2.2.1. Non-Coastal Sahel..................................................................31 2.5.2.2.2. Coastal Non-Sahel..................................................................32 2.5.2.2.3. Coastal Sahel...........................................................................33 2.5.2.3. Trends in the Availability of Major Starchy Staple Types (kg/capita/year).......................................................................................34 2.5.2.3.1. Major Starchy Staples Availability in the NonCoastal Sahel..........................................................................35 2.5.2.3.2. Major Starchy Staples Availability in the Coastal Sahel....37 2.5.2.3.3. Major Starchy Staples Availability in the Coastal NonSahel........................................................................................40 2.5.2.4. Trends in Per Capita Macronutrient Availability ..............................43 2.5.2.4.1. Analysis of Protein Supply ....................................................44 2.5.2.4.1.1 Trend in Total Daily Protein Availability Per Capita .................................................................44 2.5.2.4.1.2. Daily Protein Supply by Source-Animal versus Plant Protein .........................................46 vi 2.5.2.4.1.3 Animal Protein by Source ...............................51 2.5.2.4.1.4. Plant Protein by Source ....................................64 2.5.2.4.2. Analysis of Fat Supply ...........................................................69 2.5.2.5. Trends in the Share of Macronutrient Group in Daily Per Capita Energy Supply........................................................................................71 2.5.2.5.1. Non-Coastal Sahel ...........…………………………………..71 2.5.2.5.2. Coastal Sahel .......……………………………………...........72 2.5.2.5.3. Coastal Non-Sahel .................................................................72 2.6. Chapter Summary .........................................................................................................78 APPENDIX... ................................................................................................................................81 CHAPTER 3. AGGREGATE-LEVEL DETERMINANTS OF STARCHY STAPLES DEMAND IN WEST AFRICA: THE CASE OF BENIN, MALI AND SENEGAL ............104 3.1. Background and Problem Statement .........................................................................104 3.2. Research Objective and Hypotheses ...........................................................................106 3.3. Data and Methodology .................................................................................................107 3.4. Aggregate Food Demand Model Specification and Estimation Method ................108 3.5. Findings .........................................................................................................................116 3.5.1. Determinants of Starchy Staples Demand – Senegal .....................................116 3.5.2. Determinants of Starchy Staples Demand – Benin .......................................127 3.5.3. Determinants of Starchy Staples Demand – Mali ..........................................135 3.6. Chapter Summary ........................................................................................................143 APPENDIX.. ...............................................................................................................................146 CHAPTER 4. HOUSEHOLD-LEVEL EVIDENCE OF CEREALS DEMAND IN URBAN AND RURAL MALI ..................................................................................................................156 4.1. Background and Problem Statement .........................................................................156 4.2. Research Questions and Hypotheses ..........................................................................157 4.3. Conceptual Framework and Literature Review .......................................................159 4.3.1. Household-Level Determinants of Food Demand ..........................................159 4.3.1.1. Income ...................................................................................................159 4.3.1.2. Prices......................................................................................................160 4.3.1.2.1. Estimating Price Effects in Cross-Sectional Household Survey Data...........................................................................162 4.3.1.3. Taste and Preferences ..........................................................................164 4.3.1.4. Household Socio-demographic Characteristics ................................165 4.3.1.5. Geographic Location ...........................................................................165 4.3.1.6. Place of Residence ...............................................................................166 4.4. Data and Computation of Relevant Variables ..........................................................167 4.5. Methodological Framework .......................................................................................167 4.5.1. Commodity Aggregation and Weak Separability ..........................................167 4.5.2. Modeling Approach ...........................................................................................168 4.5.2.1. Model Specification Test ....................................................................169 4.5.2.2. Problems in Demand System Estimation ..........................................169 4.5.2.2.1. Zero-Expenditure.................................................................170 vii 4.2.5.2.2. Expenditure Endogeneity (EE) ..........................................171 4.6. Estimation Method ......................................................................................................174 4.7. Findings ........................................................................................................................175 4.7.1. General Descriptive Summary of the Data .....................................................175 4.7.2. Household Cereals Demand: Econometric Results .......................................197 4.7.2.1. Expenditure Elasticities by Place of Residence ................................204 4.7.2.2. Expenditure Elasticities by Income Group within Place of Residence ...............................................................................................205 4.7.2.3. Own-Price Responses by Place of Residence ....................................207 4.7.2.4. Own-Price Responses by Income Group within Place of Residence...............................................................................................210 4.7.2.5. Cross Price Elasticities by Place of Residence ...................................210 4.7.2.6. Cross Price Elasticities by Place of Residence and Income Group..212 4.7.2.6.1. Urban Cross Price Effects by Income Group....................212 4.7.2.6.2. Rural Cross Price Effects by Income Group......................213 4.8. Chapter Summary .......................................................................................................215 APPENDIX.. ...............................................................................................................................219 CHAPTER 5. WELFARE EFFECTS OF CEREAL PRICE SHOCKS IN MALI ............244 5.1. Problem Statement ......................................................................................................244 5.2. Research Objectives .....................................................................................................244 5.3. Literature Review .........................................................................................................245 5.4. Methodological Approach and Data ..........................................................................248 5.5 Findings ........................................................................................................................251 CHAPTER 6. SUMMARY OF MAJOR FINDINGS AND IMPLICATIONS FOR THE FOOD SECURITY POLICIES IN MALI ...............................................................................264 6.1. Summary of Major Findings and Policy Implications ..............................................264 6.2. Limitations of the Study ..............................................................................................271 BIBLIOGRAPHY ......................................................................................................................273 viii LIST OF TABLES Table 1-1. Measures of Food Availability and Consumption Used in this Study………...........13 Table 2-1. Five - Year Cumulative Population Growth Rate (%) in 1980-2010 ..........................22 Table 2-2. Average Annual Real Per Capita GDP Growth Rates..................................................25 Table 2-3. Three-Year Averages of Animal Protein Supply (kg/capita) in Non-Coastal Sahel- Burkina Faso................................................................................53 Table 2-4. Three-Year Averages of Animal Protein Supply (kg/capita) in Non-Coastal Sahel - Mali.............................................................................................54 Table 2-5. Three-Year Averages of Animal Protein Supply (kg/capita) in Non-Coastal Sahel- Niger...........................................................................................55 Table 2-6. Three-Year Averages of Animal Protein Supply (kg/capita) in Coastal Sahel............57 Table 2-7. Three-Years Average Meat Supply (kg/capita) in Coastal Non-Sahel........................60 Table 2-8. The Contribution of Pulses to Plant Protein Supply (g/capita/day) Non-Coastal Sahel.......................................................................................................65 Table 2-9. The Contribution of Pulses to Plant Protein Supply (g/capita/day)-Coastal Sahel.............................................................................................................................66 Table 2-10. The Contribution of Pulses to Plant Protein (g/capita/day) Coastal Non-Sahel.........67 Table A2-1. Food Availability by Major Food Group–Non-Coastal Sahel- Burkina Faso (Kg/capita/year)..........................................................................................................82 Table A2-2. Food Availability by Major Food Group - Mali (kg/capita/year).............................83 Table A2-3. Food Availability by Major Food Group–Non-Coastal Sahel - Niger (Kg/capita/year)........................................................................................................84 Table A2-4. Food Availability by Major Food Group - Coastal Non-Sahel- Benin (Kg/capita/year)........................................................................................................85 Table A2-5. Food Availability by Major Food Group–Coastal Non-Sahel - Cote d'Ivoire (Kg/capita)................................................................................................................86 Table A2-6. Food Availability by Major Food Group–Coastal Non-Sahel-Ghana ix (Kg/capita)................................................................................................................87 Table A2-7. Food Availability by Major Food Group–Coastal Non-Sahel – Guinea (Kg/capita)................................................................................................................88 Table A2- 8. Food Availability by Major Food Group-Coastal Non-Sahel- Liberia (Kg/capita)...............................................................................................................88 Table A2-9. Food Availability by Major Food Group-Coastal Non-Sahel -Nigeria (Kg/capita)............................................................................................................... 90 Table A2-10. Food Availability by Major Food Group–Coastal Non-Sahel- Sierra Leone (kg/capita).....................................................................................................91 Table A2- 11. Food Availability by Major Food Group–Coastal Non-Sahel – Togo (Kg/capita).............................................................................................................92 Table A2-12. Food Availability by Major Food Group - Coastal Sahel-Cape Verde (Kg/capita)...............................................................................................................93 Table A2-13. Food Availability by Major Food Group–Coastal Sahel- Gambia (Kg/capita)...............................................................................................................94 Table A2-14. Food Availability by Major Food Group–Coastal Sahel – Guinea Bissau (Kg/capita)...............................................................................................................95 Table A2-15. Food Availability by Major Food Group–Coastal Sahel-Senegal (Kg/capita)...............................................................................................................96 Table A2-16. Starchy Staples Availability (kg/capita) - Non-Coastal Sahel.................................97 Table A2-17. Starchy Staples Availability (kg/capita) in Selected Countries in Coastal Sahel...........................................................................................................98 Table A2-18. Starchy Staples Availability (kg/capita) in Selected Coastal Non-Sahel Countries...............................................................................................99 Table A2-19. Daily Protein Availability by Source (kg/capita) Non-Coastal Sahel...................101 Table A2-20. Daily Protein Availability by Source (g/capita) Coastal Sahel.............................102 Table A2-21. Daily Protein Availability by Source (g/capita) in Selected Countries in Coastal Non Sahel..............................................................................................103 Table 3-1. Descriptive Summary of Variables in the Regression - Senegal: 1990-2009............117 x Table 3-2. Tests of Regression Residuals for Unit Roots - Senegal ..........................................120 Table 3-3. Parameter Estimates from Error-Corrected Linear AIDS Model - Senegal...............123 Table 3-4. Estimated Error-Corrected Short-Run Demand Elasticities - Senegal.......................124 Table 3-5. Senegal: Estimated Error-Corrected Long-Run Demand Elasticities .......................125 Table 3-6. Benin - Descriptive Statistics of Variables in the Regression, 1990-2009.................128 Table 3-7. Tests of Regression Residuals for Unit Roots – Benin..............................................131 Table 3-8. Parameter Estimates in ECLAIDS for Starchy Staples in Benin...............................133 Table 3-9. Estimated Error-Corrected Short-Run Demand Elasticities - Benin..........................134 Table 3-10. Estimated Error-Corrected Long-Run Demand Elasticities - Benin........................134 Table 3-11. Descriptive Statistics of Variables in the Regression - Mali: 1990-2009................136 Table 3-12. Mali-Tests of Regression Residuals for Unit Roots.................................................139 Table 3-13. Parameter Estimates from Error-Corrected Linear AIDS model - Mali..................140 Table 3-14. Mali: Estimated Error-Corrected Short-Run Demand Elasticities...........................142 Table 3-15. Mali: Estimated Error-Corrected Long-Run Demand Elasticities...........................142 Table A3-1. Unit Root Tests (H0: Unit Roots) – Senegal...........................................................147 Table A3-2: Unit root tests (H0: Non-Stationarity/unit roots) - Senegal.....................................148 Table A3-3. KPSS Test for Unit Roots-Levels (H0: Stationarity) – Senegal..............................149 Table A3-4. KPSS Test for Unit Roots- First Differenced (H0: Stationarity) – Senegal............149 Table A3-5: Unit Root Tests (Non-Stationarity as the Null Hypothesis) – Benin......................150 Table A3-6. Unit root tests (Non-Stationarity as the Null Hypothesis) – Benin.........................151 Table A3-7. KPSS Test for Unit Roots-Levels (Ho: Stationarity) – Benin ..............................152 Table A3-8. KPSS Test for Unit Roots- First Differenced (Ho: Stationarity) – Benin...............152 Table A3-9. Unit Root Tests (H0: Non-Stationarity/Unit Roots) – Mali....................................153 xi Table A3-10: Unit root tests (H0: Non-Stationarity/unit roots) - Mali........................................154 Table A3-11. KPSS Test for Unit Roots-Levels (H0: Stationarity) – Mali.................................155 Table A3-12. KPSS Test for Unit Roots- First Differenced (H0: Stationarity)-Mali..................155 Table 4-1. Distribution of Data by Region and Place of Residence ..........................................177 Table 4-2. Relationship between Household (HH) Size Group and Place of Residence....................................................................................................................177 Table 4-3. Level of Education of Household Table Head(HHH) ...............................................178 Table 4-4. Distribution of Households by Sex and Age of Household Head..............................178 Table 4-5. Socioeconomic Group of Household Head by Region...............................................179 Table 4-6. Annual Average Total Consumption Expenditures (CFA franc) by Place of Residence.....................................................................................................181 Table 4-7. Annual Average Total Consumption Expenditures (CFA franc) Per Household by Income Group and Place of Residence.....................................................................182 Table 4-8. Annual Average Total Consumption Expenditures (CFA franc) per Adult Equivalent by Income Group and Place of Residence......................................182 Table 4-9. Average Annual Food and Non-Food Expenditure (CFA franc) by Place of Residence.................................................................................................183 Table 4-10. Average Annual Food and Non-Food Expenditure (CFA franc) by Place of Residence and Income Group...................................................................................184 Table 4-11. Weighted Food Expenditure Shares by Region........................................................185 Table 4-12. Weighted Food Shares by Income Group and Place of Residence..........................185 Table 4-13. Average Annual Cereals and Non-Cereals Expenditure (CFA franc) by Place of Residence and Income Group.....................................................................189 Table 4-14. Cereals Expenditure Shares by Region....................................................................190 Table 4-15. Cereal Shares by Income Group and Place of Residence.........................................190 Table 4-16. Average Annual Expenditures per Adult Equivalent by Cereal Type and Place of Residence....................................................................................................192 xii Table 4-17. Average Annual Expenditures (CFA franc/AE) by Cereal Type and Place of Residence....................................................................................................193 Table 4-18. Average Annual Expenditures (CFA franc/AE) by Cereal Type, by Income Group and Place of Residence.....................................................................194 Table 4-19. Shares in Cereal Budget by Cereal Type, Place of Residence and Income Group ......................................................................................................196 Table 4-20. Estimated Reduced Forms for Cereals Expenditure and Cereal Expenditure Squared................................................................................................200 Table 4-21. Results of the Test for the Endogeneity of Expenditure...........................................201 Table 4-22. Tests for Nonlinearity of the Demand System Based on Statistical Significance of the Coefficient of the Price Times Expenditure-Squared Terms.............................202 Table 4-23. Cereals Expenditure Elasticities by Place of Residence and Income Group............206 Table 4-24. Cereals Own-Price Elasticities - By Place of Residence and Income Group...........209 Table 4-25. Compensated Cross-Price Elasticities - By Place of Residence...............................211 Table 4-26. Urban Compensated Cross-Price Elasticities by Income Group..............................213 Table 4-27. Rural Compensated Cross-Price Elasticities by Income Group...............................215 Table A4-1. Structure of ELIM-2006 data................................................................................. 220 Table A4-2. Number of Zero Expenditures by Place of Residence-Considering Expenditure on All Modes of Acquisition.................................................................................. 226 Table A4-3. Zero-Expenditure by Mode of Acquisition.............................................................226 Table A4-4. Estimated Parameters of the Censored QUAIDS model for Cereals Demand- by Place of Residence – Total Cereals Expenditure......................................................227 Table A4-5. Estimated Elasticities of the Censored QUAIDS model for Cereals Demand by Place of Residence- Total Cereals Expenditures................................................229 Table A4-6. Estimated Elasticities of the Censored QUAIDS model for Cereals Demand by Urban- Income Group- Total Cereals Expenditures............................................231 Table A4-7. Estimated Elasticities of the Censored QUAIDS model for Cereals Demand by Rural- Income Group - Total Cereals Expenditures...........................................233 Table A4-8. Estimated Parameters of the Censored QUAIDS model for Cereals Demand xiii by Place of Residence – Only Purchased Cereals Expenditure..............................235 Table A4-9. Estimated Elasticities of the Censored QUAIDS model for Cereals Demand by Place of Residence- Only Purchased Cereals Expenditures..............................238 Table A4-10. Estimated Elasticities of the Censored QUAIDS model for Cereals Demand by Urban- Income Group- Only Purchased Cereals Expenditures.............................240 Table A4-11. Estimated Elasticities of the Censored QUAIDS model for Cereals Demand by Rural- Income Group- Only Purchased Cereals Expenditures..............................242 Table 5-1. Average Consumer Price Changes Compared to 2006 (%).......................................250 Table 5-2. Compensating Variation of Cereals Price Changes by Place of Residence (% of Total Cereals Expenditures).............................................................................251 Table 5-3. Magnitude of Welfare Loss Implied by Cereals Price Changes by Place of Residence.....................................................................................................253 Table 5-4. Compensating Variation of Cereals Price Changes by Place of Residence and Income Group (% of total Cereals Expenditures)...............................................254 Table 5-5. Magnitude of Welfare Loss Implied by Cereals Price Changes by Place of Residence and per Capita Income Group................................................................256 Table 5-6. Compensating Variation Implied by Rice Price Changes by Place of Residence (%)............................................................................................................257 Table 5-7. Magnitude of Welfare Loss Implied by Rice Price Changes by Place of Residence...................................................................................................................258 Table 5-8. Welfare Effects of Rice Price Increases by Place of Residence and Income Group (%).....................................................................................................259 Table 5-9. Magnitude of Welfare Loss Implied by Rice Price Changes by Place of Residence and per Capita Income Group..................................................................260 xiv LIST OF FIGURES Figure 1-1. Map of West Africa......................................................................................................2 Figure 1-2. Annual Food Price Index (2002-2004=100).................................................................3 Figure 2-1. Urban Population Shares (%) - West Africa (1980-2010) ...................................... ...23 Figure 2-2. Daily Energy Availability (kcal/capita/day) - Non-Coastal Sahel…………………..29 Figure 2-3. Daily Energy Availability (kcal/capita/day) - Coastal Sahel………………………..29 Figure 2-4. Daily Energy Availability (kcal/capita/day) - Coastal Non-Sahel…………………..30 Figure 2-5. Major Starchy Staples Availability - Mali (kg/capita/year) ………………………...37 Figure 2-6. Major Starchy Staples Availability - Cape Verde (kg/capita/year) ………………...38 Figure 2-7. Major Starchy Staples Availability - Senegal (kg/capita/year)……………………...39 Figure 2-8. Major Starchy Staples Availability - Ghana (kg/capita/year)……………………….42 Figure 2-9. Major Starchy Staples Availability - Nigeria (kg/capita/year)……………………...43 Figure 2-10. Protein Availability (g/capita/day) Non-Coastal Sahel……………………………45 Figure 2-11. Protein Availability (g/capita/day)-Coastal Sahel…………………………………45 Figure 2-12. Protein Availability (g/capita/day)-Coastal Non-Sahel……………………………46 Figure 2-13. Animal Protein Availability (g/capita/day) Non-Coastal Sahel……………………47 Figure 2-14. Animal Protein Availability (g/capita/day) Coastal Sahel…………………………48 Figure 2-15. Animal Protein Availability (g/capita/day) Coastal Non-Sahel……………………50 Figure 2-16. Fat Availability (g/capita/day) Non-Coastal Sahel...………………………………69 Figure 2-17. Fat Availability (g/capita/day) Coastal Sahel……………………………………...70 Figure 2-18. Fat Availability (g/capita/day) Coastal Non-Sahel………………………………...70 Figure 2-19. Daily Caloric Share (%) by Macronutrients - Non-Coastal Sahel…………………74 xv Figure 2-20. Daily Caloric Share (%) by Macronutrients - Coastal Sahel………………………75 Figure 2-21. Daily Caloric Share (%) by Macronutrients - Coastal Non-Sahel…………………76 Figure 3-1. Shares in Cereals Budget - Senegal: 1990-2009 ...................................................... 118 Figure 3-2. Natural Logarithm of Deflated Cereals Prices - Senegal: 1990-2009...................... 118 Figure 3-3. Shares in Starchy Staples Budget - Benin: 1990-2009 ............................................ 129 Figure 3-4. Logarithm Transformed Deflated Starchy Staples Prices - Benin: 1990-2009........ 129 Figure 3-5. Shares in Cereals Budget - Mali: 1990-2009 ........................................................... 136 Figure 3-6. Logarithm Transformed Deflated Cereals Prices - Mali: 1990-2009 ...................... 137 Figure 4-1. Food Expenditures per Capita and Total Household Consumption Expenditures per Capita (CFA franc)……………………………………………………….........186 Figure 4-2. Food Expenditure Shares and Total Household Consumption Expenditures .......... 187 Figure 4-3. Total Household Food Expenditure and the Share of Cereals in Food Budget ....... 191 Figure 4-4. Cereals Expenditures (CFA franc/AE) by Income Group and Place of Residence..195 Figure 4-5. Shares in Cereal Budget by Cereal Type Place of Residence and Income Group ... 196 xvi KEY TO ABBREVIATIONS ADF–Augmented Dickey-Fuller AIDS–Almost Ideal Demand System CDF–Standard Normal Cumulative Distribution Functions CFA franc–Common Currency for West African States CV–Proportional Compensating Variation DEA–Daily Energy Availability ECLAIDS–Error Corrected Linearized Almost Ideal Demand System ECOWAS– Economic Community of West African States ELIM–Enquête Légère Intégrée Auprès des Ménages FAO–Food and Agricultural Organization of the United Nations FBS–Food Balance Sheet GDP–Gross Domestic Product HBS–Household Budget Survey HH–Household HHH–Household Head IV–Instrumental Variable KPSS–Kwiatkowski–Phillips–Schmidt–Shin tests MPC–Marginal Propensity to Consume OLS–Ordinary Least Squares OMA–Observatoire du Marché Agricole PDF–Standard Normal Probability Density Function xvii PP–Phillips-Perron QUAIDS–Quadratic Almost Ideal Demand System R&T–Roots and Tubers SAP–Structural Adjustment Programs WA–West Africa xviii CHAPTER 1. INTRODUCTION 1.1. Issue and Background The region of West Africa (WA) includes 16 countries: Benin, Burkina Faso, Cape Verde, Cote d’Ivoire, Gambia, Ghana, Guinea, Guinea Bissau, Liberia, Mali, Mauritania, Niger, Nigeria, Senegal, Sierra Leone, and Togo. A map of WA is available in Figure 1-1. With the exception of Mauritania, all of these countries are members of the Economic Community of West African States (ECOWAS). This study focuses on ECOWAS member countries since ECOWAS has a major role in defining agricultural policy for the region. WA has undergone rapid changes in its social and economic environment during the last 25 years, resulting in shifts in food consumption patterns. Some of these changes include urbanization, growth in per capita incomes, population growth, in a few countries a demographic transition towards smaller family sizes, migration within the zone towards the coastal states, and the adoption of more western lifestyles (Lopriore and Muehlhof, 2003; Satterthwaite et. al, 2010). In addition to the aforementioned structural factors, the region has undergone policy shifts that constituted major changes in the conditions that determine demand. Examples of these include the Structural Adjustment Programs (SAP) and the 1994 CFA franc devaluation that brought about changes in relative cereal prices, thereby increasing the domestic price of rice relative to that of the local coarse grains (Camara, 2004). 1 Figure 1-1. Map of West Africa The 2007-2008 global food crisis brought renewed attention to food consumption patterns worldwide and in particular in developing countries. The main symptom of the crisis was a large upsurge in international prices for the main staple foods, principally maize, wheat, rice, and soybeans, thus triggering world-wide concerns about threats to global food security (Joseph and Wodon, 2008). From a global perspective, the increase in food prices has been attributed to several factors (see Kelly, et al. 2008; Joseph and Wodon, 2008, and Staatz et al. 2008). Kelly et al. (2008) also offered an explanation for the food price crisis from a Sahelian perspective, showing how the manifestation of the food crisis has been different in this region. Since 2008, world staple food prices have remained at high levels by historical standards. An 2 examination of the Food and Agricultural Organization (FAO)’s food price index (see Figure 1.2), a measure of the change in international prices of a basket of food commodities, shows that in 2011 the index rose above its 2008 peak. The index dropped in 2012 (nominal terms) but still remained generally higher than its 2008 level.1 Figure 1-2. Annual Food Price Index (2002-2004=100) 250 200 150 Real 100 Nominal 50 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 0 Source: Author’s computation using FAO’s food price index. The circumstances of the global food crisis in WA, which previously relied on cheap food imports for a substantial part of its staple food supply, have been unique.2 As observed by 1 FAO, Food Price Index: http://www.fao.org/worldfoodsituation/FoodPricesIndex/en/. The deregulation of domestic food markets and the liberalization of agriculture experienced as part of the SAP in the region forced most of West African nations into competition in the world food markets with developed country producers that produced at lower costs and sold at lower prices, sometimes due to substantial subsidies provided to their farmers and exporters. 3 2 Staatz et al. (2008), trade bans and high international food prices pushed many West African countries away from their historical reliance on regional and international trade as a key component of their food security strategies, thereby leading many governments to conclude that the risks were very high in depending on the international market for staples. Kelly et al. (2008) also observed that in the Sahel region, the impact of the food price crisis on household consumption has been differentiated according to each country’s food consumption profile and food supply. However, in spite of production shortfalls in some countries, there is a strong potential for production stability at the regional level (Kelly et al. 2008). 1.2. Problem Statement Food demand is determined by factors at the national (aggregate), the intermediate, and the household (micro) level. Aggregate-level determinants of food consumption include population, urbanization, per capita incomes and overall changes in lifestyle. Intermediate-level determinants include factors such as cultural changes that affect changes in tastes and preferences. Householdlevel factors include households’ economic and socio-demographic characteristics such as household composition (size, age and sex), income level and geographic location. Households therefore differ among themselves in food consumption behavior and, in particular, in their response to changes in market conditions. The analysis of food consumption provides information on: 1) food demand elasticities (own-price, cross-price and income elasticities); 2) differences in demand patterns by urban/rural location, by geographical region, by socioeconomic group and across households of different demographic composition. Such an analysis also provides parameters needed to understand the adjustments of consumption in the macro food economy. 4 Knowledge of food demand parameters and of how consumption patterns have changed over time is critical for informed policy making. However, in WA, information on food demand parameters is limited, thus restricting policymakers’ ability to make sound food policy decisions. One ultimate goal of the analysis of food consumption patterns is to improve the efficiency of government interventions by providing policymakers, for example, with suggestions for the design of safety nets compatible with targeting people based on the nature and extent of food insecurity. According to Kelly et al. (2008), the greatest challenge in the design of policies and programs that will help households cope with the rising food prices is the identification of vulnerable groups so that targeting would be towards the neediest and not towards the most vocal constituencies. A major concern has been that the price hikes for internationally traded food products are being transmitted to local cereals such as millet, maize, and sorghum due to substitutions in production and consumption. For instance, Joseph and Wodon (2008) observed that just as the prices of imported food products–rice and wheat—have been increasing, the prices of other foods that might be thought of as substitutes (millet, sorghum and maize) in Mali have also increased recently. They attributed this change to increases in cost of production and alternate demand for grains (animal feed). Diallo et al. (2010) found that 33% of price increases have been transmitted from international to local markets in WA, mainly for rice and wheat. However, the impact varies: countries with coastline (Guinea, Ivory Coast and Senegal) are more affected than landlocked ones (Mali, Niger and Burkina (Diallo et al. 2010). This difference is likely a result of differences in the cost of inland transport, since in absolute terms the transmission may be similar across countries. Food price transmission from international to African markets also differs across commodities (Minot, 2010). 5 Historically, cereals have represented a large share of total household consumption in the Sahel. Staatz et al. (2008) observed a growing demand for cereals in WA and attribute this to population growth, urbanization and consumers’ demand for more products (including livestock products) that require cereals as intermediate inputs as income increases. Given the importance of grains in the West African food basket, a major source of concern in the context of rising food prices is the possible reduction of consumption levels whereby households may be forced to reduce both their food consumption in response to the price surge and other longer-term nonfood expenditures in order to meet basic needs. Camara (2004) found that Bamako households engage in food consumption smoothing from seasonal shocks in real incomes at the expense of non-food commodities, of non-staple foods, and through significant substitutions among and between broad expenditure items such as health and education. Data limitations prevent an actual examination of food consumption behavior following the 2007-08 food crisis. However, using Mali’s 2006 household budget survey (HBS) data as a base year, this study examines the possible effects of cereal price shocks on household welfare for different segments of the population. Changing food consumption patterns also have implications for agricultural market development, currently a priority for WA’s development agenda. With urbanization and the growing urban middle class in WA, understanding how these patterns have changed (in level and diversity), whether new food groups are emerging as important sources of household food energy consumption and whether the traditional cereal habits persist, will help identify opportunities and challenges for the development of agricultural value chains to meet the growing effective demand. The findings of this study will contribute to the knowledge base and policy dialogue at regional and national levels on key policy issues concerning the evolution of agri-food systems. 6 1.3. Research Objectives The overall objective of this study is to investigate the trends and determinants of food availability and consumption patterns in WA. The study is based on three major hypotheses: i) over time there have been changes in the levels and the composition of consumption resulting from changes in structural factors like urbanization and increases in per capita incomes; ii) household food consumption behaviors are influenced by market conditions (food prices), household social, economic and demographic characteristics as well as the geographic region and place of residence of the household; and iii) the welfare effects of a food price change varies across households of different characteristics. The specific objectives of the study are:  To describe aggregate-level trends in per capita food availability in WA in the period 1980-2009 (Chapter 2).  To estimate aggregate-level determinants of starchy staples demand in selected countries in WA (Chapter 3).  To estimate food demand parameters for urban and rural Malian households (Chapter 4).  To examine the welfare effects of cereal price shocks on cereal demand (Chapter 5).  To draw some implications for food security policy decisions (Chapter 6). 1.4. Literature Review and Research Gap Numerous research efforts have been made over time to understand shifts in food consumption patterns in WA. These efforts were undertaken in 3 major eras: 1) the 1980s and early 1990s (pre-CFA franc devaluation); 2) post-1994-CFA franc devaluation through 2006; and 3) the period following the 2007-2008 food price crisis. Generally, these studies have sought to provide aggregate and micro-level evidence of shifts in food consumption. 7 The 1980s and early 1990s was a period characterized by heavy reliance on imports for household food grain needs. The heavy reliance was attributed to the declining competitiveness of WA food production relative to other producers in the world. A major research question during the 1980s and 1990s was whether the high consumption of imported rice and wheat was caused by relatively low rice and wheat prices. A key finding during this period was that the consumption of imported grains (especially rice) was not driven by relative cereal prices (Reardon et al. 19883 ; Delgado, 19894; and Rogers and Lowdermilk, 19915). According to Delgado and Reardon (1992), the switch to rice consumption in the West African Semi-Arid Tropics appeared to be driven more by structural factors than by shorter-run factors such as harvest shortfalls or price dips. They concluded that rice and wheat prices would have to increase very substantially over those of millet and sorghum before encouraging shifts in consumption back to coarse grains. The 1994 devaluation of the common currency of many West African countries represented a major policy shift that changed the conditions that determine demand. An intended consequence of the devaluation was to raise the costs of all tradable goods relative to nontradable goods and reverse the trend in cereal demand from imported to locally produced grains. Evidence based on post-devaluation studies suggests relatively low rates of substitution of coarse grains for rice in urban centers of the Sahel. Diagana et al. (1999) studied urban WA consumption patterns (Mali, Burkina Faso, Senegal and Cote d’Ivoire), and they found that the general pattern was a reduction in cereal intake (actual quantity consumed in kilograms), but the 3 Using data household-level data from urban Burkina Faso. Using country level data for Burkina Faso, Cote d’Ivoire, Mali, Niger and Senegal. 5 Using household-level data from urban Mali. 8 4 expected shift from imported rice to local coarse grains as a result of price hikes for imported cereals did not occur in these countries, with the exception of Burkina Faso. The lack of such a shift was attributed to the lackluster supply response of the coarse grain sectors and the resilience of rice demand based on its convenience of processing and preparation for the urban consumer. Camara (2004) investigated the impact of seasonal changes in real incomes and relative prices on households’ consumption patterns in Bamako, Mali. She found that Bamako households’ consumption patterns are responsive to changes in real incomes and relative prices in any given season and that there are seasonal changes in income and price responsiveness for all commodities in the three demand models she estimated. Evidence on food consumption patterns in WA following the 2007-2008 food price crisis is relatively thin. Joseph and Wodon (2008) examined patterns of food consumption in Mali to understand differences across households groups as defined by their level of consumption and, in particular, the differential impact on poverty of higher food prices. They assumed that the cost of an increase in the price of a food commodity for a household translates into an equivalent reduction of its consumption in real terms (unit-own price elasticity). They neither estimated nor took into account the own-price or cross-price elasticities of demand, which may lead to substitution effects and thereby help offset part of the negative effect of higher prices for certain food items. They assumed constant relative prices and argued that the substitution of millet, sorghum, and maize for rice and wheat is likely to be low in any case, due to the fact that all these products are important in the diet of the population and that the prices of the various food items seem to increase in parallel at least in the medium term (so that it is not clear that households can offset the loss in purchasing power associated with the price increase by shifting 9 to other foods). They admitted the roughness of their approach and the possibility of slightly overestimating the impact on poverty of changes in prices. Taondyandé and Yade (2012) examined, using descriptive and econometric approaches, how food consumption patterns had changed over time with increased per capita incomes and the growth in urban population. They also examined how food demand prospects would likely change as a result of changes in per capita income and by place of residence. Specifically, they estimated the additional demand for food (marginal propensity to consume, MPC) from an increase in per capita income as well as income elasticities. However, they do not control for price variation across the sample. 1.5. Research Contributions The aim of the current study is to build on the Taondyandé and Yade (2012) study in four important ways. Firstly, this study examines aggregate (national) level trends in food availability patterns from national official statistics (as reported through FAO’s FBS). In particular, this analysis will help us identify major contributors to food availability as well as identify any new food groups emerging as important contributors to food availability in the region. Secondly, the study examines aggregate-level determinants of starchy staples demand in selected countries using a theoretically appropriate framework of analysis. In particular, aggregate-level demand parameters are obtained by estimating, separately for each of the countries considered, the impact of the structural variables and prices on startchy staples expenditures. Aggregate-level food demand analysis provides an understanding of the linkages between macroeconomic performance and food consumption and, through the food marketing sector, incentives for agricultural production. Overall, such an analysis provides a context in 10 which to discuss more narrowly defined changes in food consumption patterns from micro-level analysis. Thirdly, the current study seeks to provide estimates of price and income elasticities of demand for key food items using household-level data from Mali. Taondyandé and Yade (2012), in their estimates of the MPCs disaggregated by place of residence, ignore the effect of factors other than income that could influence household consumption. Effective design of targeted actions requires knowledge of the distribution of the effects of changes in income as well as factors other than income that determine food demand—food prices being an important one. The current study thus seeks, by means of a multivariate econometric analysis, to investigate the combined effects of the factors influencing food demand, especially for cereals, in Mali. The parameters of the multivariate food demand analysis (i.e., own-price, cross price and income elasticities) are useful in: 1) characterizing the nature of the different food items (inferior vs. normal) and 2) in computing welfare measures of the effects of cereal price shocks. Both of these serve as vital inputs into characterizing households according to their level of vulnerability to cereal price shocks (and hence vulnerability to food insecurity, given the important role that cereals play in satisfying minimum household food security needs), and in making enlightened suggestions for food security policy. The last contribution of this study is that it examines the welfare effects of cereal price shocks on cereal demand and draws some implications for food security policy decisions. The remainder of this study is structured as follows: Chapter 2 examines aggregate-level trends in food availability in the ECOWAS member states of West Africa; Chapter 3 examines aggregate-level food demand determinants in Mali, Senegal and Benin; Chapter 4 examines household-level food demand in urban and rural Mali; Chapter 5 examines the welfare 11 implications of cereals price shocks for urban and rural Malian households; and Chapter 6 provides a summary of findings and policy implications. Table 1-1 summarizes the different measures of food availability, expenditure and consumption used in this study. It is important to note that each of these indicators measures a different aspect of per capita access to food, and care must be taken not to equate the different measures (e.g., assuming that per capita food availability, as measured by food balance sheets, indicates actual food intake). 12 Table 1-1. Measures of Food Availability and Consumption Used in this Study Measure Description Food Measures the annual quantity (kg/capita) of Availability per food supply by commodity and also major capita food groups. This measure is computed by dividing total food supply available for human consumption (thousands of metric tons) for each year by the population for that year. The result is a proxy for foods actually consumed and is particularly useful for examining trends over time. Total food supply for human consumption for each year is in turn computed by deducting from the total domestic supply for each commodity the quantities channeled to other uses–feed, seeds, processing, and other modes of utilization. Domestic supply reflects total annual food production, imports, stocks of commodities, subtracting exports. Food availability data do not, however, typically account for losses through spoilage, plate waste, food preparation practices, or other factors. As a result, they may overestimate consumption. Macronutrient Measures the quantity of major macronutrient groups–essentially proteins Availability and fats, available for human consumption per capita (grams/capita/day) Measures actual consumption expenditures Food Consumption for different food commodity groups at the household-level. It includes the total value, Expenditures in local currency, of food purchased by commodity group, the value of food consumed from own-production, as well as the value of food from other modes of acquisition (e.g., gifts and celebrations). 13 Data Source Chapter FAO’s–Food Balance Sheet Chapters 2 and 3 FAO’s–Food Balance Sheet Chapter 2 and 3 Mali’s 2006 Chapters 4 Household and 5 Budget Survey (ELIM-2006) CHAPTER 2. TRENDS IN PER CAPITA FOOD AVAILABILITY IN WEST AFRICA 2.1. Introduction Understanding how patterns of per capita food availabilty have changed with changes in urbanization, per capita incomes, population growth, migration within the zone towards the coastal states, and the adoption of more western lifestyles is necessary in identifying opportunities and challenges for the development of agricultural value chains to meet the growing effective demand in the region. Lopriore and Muehlhoff (2003) documented the most recent evidence (prior to this study) on aggregate per capita food availability patterns in WA from food balance sheets (FBS). They analyzed trends in dietary energy supply and also in the quality and diversity of per capita food supplies. However, their analysis covers only up to the year 2001. This chapter expands and updates the Lopriore and Muehlhoff analysis by providing a more comprehensive and up-to-date picture of the trends in per capita food availability in WA, discussing what is happening in the “big drivers” of change in the region (e.g., Nigeria and Ghana) as well as analyzing shifts in per capita food availability in the context of the social, economic and political changes that have occurred in the region. 2.2. Objectives and Hypotheses This chapter investigates from national official statistics (as reported through FAO’s FBS) aggregate (national) trends in per capita food availability in WA in the period 1980-20096. The analysis is carried out on the 15 ECOWAS member states, and it will help identify major 6 Most recent FAO food balance sheet data are of 2009. 14 contributors to the national food supply (in terms of the major food commodities) as well as new food groups emerging as important contributors to the diet. The analysis is intended to test the following hypotheses: Hypothesis 2.1: As a result of rising per capita incomes, there has been an increase in the level of per capita calorie availability in the past 30 years. Hypothesis 2.2: In the past 30 years, there has been a diversification in the composition of food supply, whereby new food groups (e.g., roots and tubers in the non-coastal Sahelian West African countries and maize in the landlocked countries) are emerging as important contributors to the daily caloric supply. Hypothesis 2.3: The contribution of animal protein to total daily protein supply has increased over time as per capita incomes have increased. Hypothesis 2.4: Based on FAO’s recommended daily allowances of various nutrients for a balanced diet, the per capita food supply has become more balanced in terms of macronutrient composition. 2.3. Data and Reliability of Food Balance Sheet Consumption Estimates Data for the period 1980-2009 per country obtained from FAO’s FBS are used for the analysis of aggregate-level trends in per capita food availability. The FBS calculate domestic food supply as production plus imports, plus stocks, and less exports. Not all domestic supply is available as food for human consumption due to other uses – feed, seeds, processing and other modes of utilization. These are deducted from the total, and the remaining supply for food use is converted into estimated per capita availability by dividing the total by an estimate of the country’s 15 population. The physical amounts of food available per person are then converted into per capita availability of calories, protein and fat using a food composition table. The reliability of the FBS as a source of national average per capita food availability estimates has been questioned. For instance, Farnsworth (1961) examined the statistical shortcomings in the construction of food balances and argued that the FBS figures on per capita availability depend on the accuracy of the production, stocks, and population figures, all of which are subject to varying degrees of error across countries. She noted that the cassava production figures deserve special attention, because they illustrate a peculiarly difficult balance sheet construction problem encountered in many African countries. Unlike practically all other staple foods, mature cassava can be harvested at any time over a period of years. Moreover, since cassava usua1ly ranks as a non-preferred food, and since it is often planted for price specu1ation and as a "hungry season" reserve, large quantities are never harvested but remain on land abandoned to bush fallow. Hence, if cassava production is estimated by applying data on sampled yields per acre to the total acreage under cassava, the result is inevitably an inflated "potential production" figure, rather than an indication of the crop harvested in a single year. Farnsworth acknowledged that some allowances were made for this peculiar “cassava estimation problem”, as well as for other balance sheet uncertainties, and she presents some other caveats on the using FBS data to estimate actual per capita food consumption. These include:  The FBS estimates measure "net availability" or "net supplies" of food at the so-called "retail level," and this includes not only food delivered to retail outlets and restaurants, but also food bartered, given away, or immediately eaten after harvesting. 16  The estimates represent the broad pattern of total food supplies, and while the estimates indicate important calorie contributors, the data afford no firm basis for determining which of the most important food groups furnishes the largest (or smallest) number of food calories.  The estimates show whether the hypothetical "average person" of a given country customarily consumes much or very little meat or milk as compared with “average persons" in other countries; whether the specified country depends very heavily or very little on the typical "cheap foods"–cereals and major starchy roots and tubers; whether wheat, rice or some specified cheaper grain is the dominant cereal; and what kind of starchy roots and tubers are most common.  For many low-income countries, the national average pattern of consumption represents a composite of several distinctly different types of diets consumed by different subgroups of the population (e.g., regional subgroups in Nigeria) and as a result may not yield the best information on subgroup diets (available from good dietary surveys that are representative samples of the population, with complete food coverage and taking adequate account of varying seasonal patterns of consumption).  The estimates often reflect the underestimation or overestimation of agricultural production –a characteristic of the agricultural statistics of practically all countries. The underestimation could be from incomplete coverage (of crop areas or crops) or taxrelated purposes (particularly in low-income countries where taxes are often tied directly or indirectly to farm output). Such crop reporting deficiencies are much greater for subsistence crops than for commercial crops, and greater for minor than major crops, and greater for secondary successive and mixed crops than for single primary crops. 17 Overestimation occurs in some countries, when (1) pre-harvest sampling methods are employed without appropriate adjustment for later losses, and (2) government officials fabricate or "adjust" yield and production figures primarily for the purpose of impressing either the voting public or their own superiors.  The estimates are at their worst when constructed for individual years and accepted as evidence of year-to-year changes in consumption. Only the largest indicated annual changes, say 20 per cent or more, can be relied on as reflections of actual variations in food consumption in most countries, and even these only as indicators of the direction, not the magnitude of change.  The estimates at the “retail level" are not the same as the estimated nutrient intake due to losses and waste. Furthermore, nutrient losses and waste beyond the “retail level" vary markedly from country to country, from commodity to commodity7, from year to year (depending mainly on weather conditions and crop quality), and from times of food shortage to times of plenty. Farnsworth acknowledged that the FAO estimators employ a uniform 15 per cent allowance for such losses. Farnsworth wrote her piece of work more than half a century ago. While some of the concerns about the manner in which FBS are constructed may still be valid, it is also most likely true that national agricultural statistics have improved substantially over time in the estimation of food availability. Nonetheless, her caveats about FBS data still need to be borne in mind. For 7 For example in tropical countries heavily dependent on root crops, plantains, and maize, not only do such foods deteriorate rapidly after harvest in hot, moist climates, but some of the lessdesired staples, like cassava, may be so amply available that they are wastefully prepared for consumption in producing areas. 18 example, a question can be raised about the extent to which any apparent diversification of the food supply over time shown by the FBS reflects real diversification versus just an improvement in the ability of national agricultural statistics to capture production of secondary crops (particularly non-cereal production). Notwithstanding the criticisms of food balance sheets, Timmer et al., (1983) argued that the analysis of FBS is the starting point for most food policy analysis at the country level. Lopriore and Muehlhoff (2003) also observed that although the analysis of food supply data derived from FAO’s FBS do not provide information on consumption patterns and tend to overestimate intakes, it can be used to describe the trends in the structure of a national diet in terms of the major food commodities. Smith and Haddad (2000) also argued that per capita daily energy availability (DEA) from the FAO’s FBS is one of the main indicators of national food availability. The authors provide empirical evidence suggesting that there is a strong correlation between this per capita DEA and more individual-based indicators of food security (e.g., anthropometric indicators of children’s nutritional status). In particular, Smith and Haddad (2000) show that national caloric availability was responsible for more than a quarter of reductions in child malnutrition in developing countries over the period 1970-95. 19 2.4. Methodological Approach Food supply data from the FAO’s FBS is used to describe aggregate trends in the structure of per capita food availability, by country, in terms of the major food commodities. The FAO’s FBS shows national and per capita quantities of food available for human consumption for almost all food commodities and all countries. The FBS also shows data on per capita food energy availability as well as the availability of individual macronutrient groups (proteins and fats). The analysis of protein availability by source and fat supply helps to better understand changes in the quality of the food available in terms of major macronutrients. With data on per capita availability of individual macronutrients and information on the nutrient conversions for each macronutrient8, the caloric (or energy) contribution of proteins and fats are calculated. According to FAO (2000), the healthy range of macronutrient intake (what FAO calls “a balanced diet”), expressed as a percent of total energy, can be broad: 55-75% from carbohydrates, 15-35% from fats and 10-15% from proteins. For these key variables, three-year averages are computed to facilitate comparison. In most cases, the results are presented by specific sub-regions in ECOWAS-WA. These include the Non-Coastal Sahel (Mali, Burkina Faso and Niger); the Coastal Sahel (Cape Verde, Gambia, Guinea Bissau, Senegal); and the Coastal Non-Sahel (Benin, Cote d’Ivoire, Ghana, Guinea, Liberia, Nigeria, Sierra Leone and Togo). The analyses are structured as follows: (i) trends in energy availability (supply)9; (ii) trends in the composition of food availability; (iii) trends in macronutrient availability; iv) trends in the contribution of plant and animal sources to protein 8 9 The general rule is that protein and carbohydrates contain 4 kcal/gm and fat contains 9 kcal/gm. Availability and supply mean the same thing in this context and are used interchangeably. 20 availability, and v) trends in the share of macronutrients in food supply. The discussion of findings includes a presentation of the major trends in per capita availability, paying attention to what is happening in the “big movers” in the region, and providing details, as necessary on the three countries (Benin, Mali and Senegal) for which aggregate demand determinants are later estimated in chapter 3 of this study. For detailed country-specific trends, the reader should look at Me-Nsope and Staatz (2013). 2.5. Findings First, the trends in the major structural factors hypothesized to influence trends in food consumption–population growth, urbanization, prices and economic growth—are examined. Second, the trends in per capita food availability from FAO’s FBS are discussed. 2.5.1. Determinants of Food Consumption Patterns 2.5.1.1. Population According to the United Nations (2011)10, the 15 West African States that constitute ECOWAS have a population of approximately 250 million people, covering an area of roughly 5 million km². The average annual population growth rate is reported at 3%, and it is forecasted that the sub-region’s population will reach 430 million by 2020. Five-year cumulative population growth rates in the period 1980-2010 reveal positive continual growth for almost all countries in the region (Table 2-1). The 2010 population figures reveal the overwhelming importance of the coastal countries (especially Cote d’Ivoire, Ghana and Nigeria) in the region’s total population. 10 http://www.ohchr.org/EN/Countries/AfricaRegion/Pages/WestAfricaSummary1011.aspx 21 Nigeria alone accounts for over half of the region’s total population, thus making her a major influence in the sub region as far as food demand is concerned. The size of the consumer population obviously has an effect on aggregate food demand since food is a basic necessity. It is also anticipated that, increasingly in the future, the population of WA will be along the coast due to substantial out-migration from the inland countries of the Sudano-Sahelian belt (e.g., Burkina Faso and Mali) to the coastal countries in WA 11 . The occurrence of such a shift is hypothesized to have important consequences on how consumption patterns for the region as a whole evolve. Table 2-1. Five - Year Cumulative Population Growth Rate (%) in 1980-2010 Country 1980 to 1985 1985 to 1990 1990 to 1995 1995 to 2000 2000 to 2005 2005 to 2010* Total Population 2010(000) Share in Regional Total in 2010 2.9% 5.5% 0.2% 6.6% 0.6% 8.1% 3.3% 0.5% Benin 2.7 2.9 3.4 2.9 3.2 3.0 8,850 Burkina Faso 2.5 2.6 2.7 2.8 2.9 2.9 16,469 Cape Verde 1.8 1.2 2.5 2.0 1.6 2.2 496 Côte d'Ivoire 4.2 3.5 3.2 2.4 1.7 1.8 19,738 Gambia 4.0 4.6 3.1 2.8 3.0 2.6 1,728 Ghana 3.3 2.8 2.8 2.4 2.4 2.0 24,392 Guinea 2.2 3.1 5.5 2.0 1.6 2.2 9,982 Guinea2.0 2.0 2.0 2.0 2.0 3.0 1,515 Bissau Liberia 2.8 -0.8 -0.3 6.1 2.2 4.5 3,994 1.3% Mali 2.0 1.6 2.5 2.8 3.1 3.0 15,370 5.1% Niger 2.8 2.9 3.3 3.5 3.5 3.5 15,512 5.2% Nigeria 2.6 2.6 2.4 2.3 2.5 2.3 158,423 52.7% Senegal 2.8 3.0 2.9 2.6 2.7 2.5 12,434 4.1% Sierra Leone 2.3 2.4 -0.4 1.2 4.4 2.0 5,868 2.0% Togo 3.4 3.0 2.2 3.2 2.4 2.7 6,028 2.0% *Growth rates up to 2005 were calculated from FAO’s Population Statistics, while the growth rates for 2005-2010 were taken from the United Nation’s population statistics. 11 http://www.unep.org/dewa/africa/publications/aeo-1/120.htm 22 2.5.1.2. Urbanization The population of WA is not only growing; it is becoming increasingly more urban. In WA, 85% of the population lived in rural areas in 1960 but by 2020, the urban-rural ratio is expected to be around 60:40 %12. In 2010, roughly 137 million people lived in urban areas, as against 170 million rural dwellers. Figures for 2010 reveal urban population shares of over 40% for 10 out of the 1615 ECOWAS countries, and a share above 50% for 5 of the 15 (Figure 2-1). The urban population share grew by more than 100% in the period 1980-2010 in 3 of the 15 ECOWAS countries (Burkina Faso, Cape Verde and Gambia); and by greater than 50% in an additional 7 of the 15 ECOWAS countries (Benin, Ghana, Guinea Bissau, Liberia, Mali, Nigeria and Togo). Figure 2-1. Urban Population Shares (%) - West Africa (1980-2010) 70 Share (%) 60 50 1980 40 1985 30 20 1990 10 1995 0 2000 23 Togo http://westafricainsight.org/articles/PDF/92 Sierra Leone 12 Senegal Nigeria Niger Mali Liberia Guinea-Bissau Guinea Ghana Gambia Côte d'Ivoire Cape Verde Burkina Faso Benin Source: Author’s compilation using data from World Bank, 2013. 2005 2010 The descriptive results presented later in this chapter provide some insight on how food availability in levels and composition is evolving with the growth in the urban population. The econometric results presented later in Chapter 3 also serve to provide evidence of any statistical association between the growth in urban population share and starchy staples availability per capita. 2.5.1.3. Economic Growth Changes in consumption patterns have also been associated with changes in a nation’s per capita gross national product. In economic theory, the relationship between food consumption and income levels is characterized by Engel’s law–the proportion of income spent on food falls as income rises. The evolution in real per capita gross domestic product (GDP)–an indicator of purchasing power, in the region reveals an overall positive trend over the period 1980-2010. Increases in average annual real per capita GDP growth rates are particularly large in the 2000s (Table 2-2). With the exception of a few countries (Cote d’Ivoire, Guinea Bissau, Liberia, Guinea and Togo), per capita GDP has been growing for most countries since 2000, and the growth rates have been largest for Cape Verde, Ghana, Nigeria, Burkina Faso, Mali and Sierra Leone. Regmi and Dyck (2001) observe that urbanization is closely related to economic development and that both interact to bring about important changes in the composition of consumption—the specific effects of urbanization on consumption differ depending on the economic conditions. Urbanization may result in an overall increase in per capita consumption, could result in improvement in diet quality (such as an increase in animal protein consumption), and could also increase the demand for processed or easy-to-prepare food (Regmi, 2001). 24 Table 2-2. Average Annual Real Per Capita GDP Growth Rates Country 1980-85 1985-90 1990-95 1995-00 2000-05 2005-10 Benin -2.0 -1.1 1.2 1.9 0.8 1.9 Burkina Faso 0.5 0.5 1.5 4.1 3.0 2.8 Cape Verde 3.2 1.3 2.4 5.8 3.4 5.8 Côte d'Ivoire -3.0 -1.9 -0.7 -0.3 -1.7 1.4 Gambia, The -0.9 -0.7 -1.5 2.2 1.5 3.7 Ghana -5.0 2.2 2.1 1.7 2.4 4.2 Guinea -0.3 1.3 -0.7 1.9 -0.2 0.7 Guinea-Bissau -0.1 0.7 1.1 -5.9 -3.4 -0.1 Liberia n/a n/a n/a n/a -7.0 4.9 Mali -3.4 3.5 0.0 1.5 3.9 2.2 Niger -6.0 -0.6 -4.5 -0.1 2.2 1.3 Nigeria 1.0 -1.9 -2.2 0.5 7.7 4.4 Senegal -0.1 -0.7 -0.6 1.5 2.1 2.4 Sierra Leone -2.5 0.0 -7.5 -11.9 10.3 3.9 Togo -4.3 0.7 -2.9 -1.4 -1.5 0.9 Source: Author’s computation using per capita GDP (constant prices), national currency from the International Monetary Fund, World Economic Outlook Database, April 2008 2.5.2. Trends in Per Capita Food Availability This section examines explores the trends in per capita daily energy availability; the supply of food by major food groups; the supply of major starchy staples; the supply of macronutrients (protein and fat) per capita; and the share of individual macronutrient groups in daily food energy supply. 2.5.2.1. Trends in Daily Food Energy Availability (kcal/capita) Per capita daily energy availability (DEA) has been widely used in the literature as one of the main indicators of national food availability (Smith and Haddad, 2000). As a national average, 25 DEA is an imperfect indicator of the state of individual food security. However, empirical evidence, such as that provided by Smith and Haddad (2000), suggest that there is a strong correlation between this per capita DEA and more individual-based indicators of food security (e.g., anthropometric indicators of children’s nutritional status). In particular, Smith and Haddad (2000) show that national caloric availability was responsible for more than a quarter of reductions in child malnutrition in developing countries over the period 1970-95. The positive growth in per capita incomes in the region over time (Table 2-2) is expected to have had a positive influence on DEA per capita. The empirical data reveal an overall positive trend in reported total per capita DEA, particularly in the last two decades (Figures 2-2, 2-3, and 2-4). Burkina Faso, Mali, Ghana, and Nigeria experienced the largest growth (in relative terms) in reported per capita DEA (50% or more) between 1980-85 and 2004-09. Cote d’Ivoire and Liberia in the same period experienced a decline in per capita DEA. The analysis of the trend in per capita DEA reveals that although the overall pattern for all countries in the region shows a shift towards greater calorie availability, the magnitude of growth has greatly varied and has been influenced by factors specific to each country. The analysis highlights the possible effect of growth in income on per capita DEA. In the NonCoastal Sahel (Figure 2-2) for instance, Mali and Burkina Faso, with modest economic growth, have also shown modest increases (in absolute terms) in per capita DEA over time. Reported per capita DEA for Mali had the biggest growth in the early and mid-1980s. Compared to the period 1983-85 (characterized by drought and economic crisis in Mali), the period 1986-1988 was characterized by good harvests and improved economic performance (growth in real per capita incomes of about 3.5%), which corresponded with growth in per capita DEA of about 18%. Mali 26 also experienced declines in reported per capita DEA in the early and mid-1990s; this was the period characterized by the initially disruptive coup d’état that took place in 1991. The 1994 CFA franc devaluation may also initially have reduced per capita purchasing power. Real per capita income data (Table 2- 2) in this period also shows very little positive growth. These factors together could explain the very modest change in per capita DEA observed during the same period. In the Coastal Non-Sahel (Figure 2-4), Ghana has shown a strong economic performance in the past 15 years, and this has been accompanied by a remarkable performance in terms of increasing per capita DEA. Similar to Ghana, Nigeria experienced strong economic growth accompanied by remarkable positive changes in per capita DEA. Cote d’Ivoire was first in terms of per capita DEA in the Coastal Non-Sahel until the early 1990s. The high reported per capita DEA during this period in Cote d’Ivoire is explainable by the economic growth enjoyed by the country in the 1970s and 1980s from a vibrant agricultural export market. Per capita DEA, however, stagnated between the periods 1992-1994 and 2001-2003, which was also a period of economic stagnation and increasing civil strife in the country. In the Coastal Sahel (Figure 2-3), Senegal experienced a declining trend in reported per capita DEA in early and mid-1980s. The drop in per capita DEA in the 1980s is likely explainable by the overall drop in GDP in Senegal during this same period, attributable in part to declining proceeds from groundnuts export sector, which fueled the economy of Senegal in the 1960s and 1970s, but has been undergoing crisis since 1987. However, since the early 2000s, reported per capita DEA has been on the rise in Senegal, as per capita incomes show some positive changes. 27 The analysis also highlights the differences in the trend in per capita DEA in countries that have experienced civil disruption, like Liberia, Sierra Leone, and Cote d’Ivoire. In Liberia for instance, between 1986-88 and 2001-2003, reported per capita DEA fell. This declining pattern in per capita DEA in Liberia reflects the debilitating effect of multiple civil wars that the country experienced in the 1990s and in the early 2000s. The positive trend in per capita DEA post 2003 reflects the end of the war in 2003 and a transition of Liberia into post-conflict reconstruction, and into medium-term growth and poverty reduction strategies13. In Sierra Leone also, the decline in per capita DEA in 1989-1991 coincided with the beginning of civil war that lasted from 1991-2002. However, since the period 2001-2003, reported per capita DEA has been rising in Sierra Leone, and this could be attributed to the positive trend in per capita GDP and the end of the civil war in the same period. Overall, based on the observed trend in per capita DEA in this study, one can say that there have likely been some improvements in the state of food security, measured in terms of food availability, over the last three decades. Additionally, the rate of growth in per capita DEA has been influenced by growth in overall economic performance and the political stability of the countries. 13 http://www.africaneconomicoutlook.org/en/countries/west-africa/liberia/ 28 Figure 2-2. Daily Energy Availability (kcal/capita/day) - Non-Coastal Sahel 3000 1980-82 kcal/capita/day 2500 1983-85 1986-88 2000 1989-91 1992-94 1500 1995-97 1000 1998-00 2001-03 500 2004-06 0 MALI NIGER BURKINA FASO 2007-2009 Source: Author’s computation using data from FAO’s Food Balance Sheets. Figure 2-3. Daily Energy Availability (kcal/capita/day) - Coastal Sahel 3000 1980-82 2500 1983-85 1986-88 2000 1989-91 1992-94 1500 1995-97 1000 1998-00 2001-03 500 2004-06 2007-2009 0 CAPE VERDE GAMBIA GUINEA BISSAU SENEGAL Source: Author’s computation using data from FAO’s Food Balance Sheets. 29 Figure 2-4. Daily Energy Availability (kcal/capita/day) - Coastal Non-Sahel 3500 kcal/capita/day 3000 1980-82 2500 1983-85 2000 1986-88 1500 1989-91 1992-94 1000 1995-97 500 1998-00 0 2001-03 2004-06 2007-2009 Source: Author’s computation using data from FAO’s Food Balance Sheets. 2.5.2.2 Trends in the Composition of Per Capita Food Availability by Major Food Group This sub-section examines aggregate shifts in per capita food supply by major food group. Specifically, it examines whether there has been a diversification in the composition of food supply, whereby new food groups (e.g., starchy roots and tubers (R&T) in the non-Coastal Sahel) are emerging as important contributors to the reported per capita DEA. There are some differences in major food groups across sub-regions. However, the most common food groups in this analysis are cereals (excluding beer), starchy R&T, fruits (excluding wine), vegetables, vegetable oils, meats and offal, alcoholic beverages, oilcrops, sugars and sweeteners, pulses, milk (excluding butter), and fish and seafood. The trend in a major food group, say “starchy R&T,” may not reflect what changes are taking place with respect to the supply of a specific 30 starchy R&T type (e.g., cassava or potatoes). The next sub-section examines trends in specific commodities within major staple food categories. 2.5.2.2.1. Non-Coastal Sahel Cereals are the dominant food group in the Non-Coastal Sahel. Per capita cereals availability (in terms of kg/person) increased by 44% for Mali (Table A2-2 in Appendix), 55% for Burkina Faso (Table A2-1 in Appendix), and by only 3% in Niger (Table A2-3 in Appendix) during the study period. Mali alone experienced an increase in per capita availability of starchy R&T in this subregion. Per capita starchy R&T supply declined in Burkina Faso (56%) and Niger (57%), albeit from small initial levels. Niger experienced the largest positive change in per capita availability of vegetables—from an average of 16 kg/capita/year in the period 1983-1985 to 51 kg/capita/year in 2007-2009 – an increase of 170% in the study period. In Mali, vegetable supply increased by 4%, while Burkina Faso experienced a decline of 27 %, in the study period. Reported availability of fruits rose in Niger (93%) and Mali (71%), while Burkina Faso experienced a decline of 38%. Reported per capita supply of meats and offal increased by 45% for Mali, 85% for Burkina Faso and 12% for Niger in the period from 1980-85 through to 20042009. A possible explanation for the higher supplies and higher rate of growth in the per capita supply of meats and offal in Mali and Burkina compared to Niger is the higher per capita incomes in Mali and Burkina Faso and economic stagnation in Niger. In contrast, in Niger, consumers appear to have relied more on pulses (particularly cowpeas) as a major, and lowercost, source of protein in the diet. Per capita supply of pulses increased in Niger by 44% in the period 1980-85 to 2004-09. In this sub-region, per capita supply of alcoholic beverages is highest 31 for Burkina Faso–and has generally remained above an average of 50 kg/capita/year in that country. 2.5.2.2.2. Coastal Non-Sahel Starchy R&T compete with cereals as major calorie sources in this sub-region. Cereals supply per capita has been on the rise for all countries in this sub-region. For all Coastal Non-Sahelian countries except Sierra Leone, starchy R&T supply has been greater than 100 kg/capita/year since the 1980s. Ghana (Table A2-6 in Appendix) and Nigeria (Table A2-9 in Appendix ) experienced the most noticeable growth in per capita supply of starchy R&T (72% and 117% respectively), and in both countries starchy R&T supply was about double that of cereals. The sharp increase in the supply of starchy R&T per capita in Nigeria from an average of 111 kg/year in 1986-1988 to 231 kg/year in 1992-1994 reflected the “cassava revolution” in Nigeria (Nweke et al., 2002). Ghana experienced an increase in per capita supply of almost all major food groups in the study period. Fruit supply per capita increased dramatically from an average of 86 kg/year in the period 1980-85 to 147 kg/year in 2004-09, an increase of 72%; meats and offal supply increased by about 22% (absolute supply stayed below 15 kg/capita/year); milk supply per capita rose by about 129%; vegetable oil supply increased by 55%; fish and seafood by 36%; and the supply of alcoholic beverages rose by about 26%. Nigeria, on the other hand, experienced a decline in per capita supply of meats and offal of 12%. However, the per capita supply of pulses (a source of high-quality protein) increased dramatically in Nigeria by 138%. Vegetable oil supply per capita also increased by 50% in Nigeria. 32 2.5.2.2.3. Coastal Sahel In the Coastal Sahel, cereals are still a major food group. Based on per capita availability, other major food groups in this region are fruits and vegetables, meats and offal, milk, sugars and sweeteners, fish and seafood. Although cereals are a major component of food availability in this sub-region, over time, per capita cereals supply did not change very much. Compared to the Coastal non-Sahel sub-region, the per capita supply of starchy R&T is much lower in this subregion. In Cape Verde, the starchy R&T supply per capita increased by 69% in the study period (Table A2-12 in Appendix). Senegal also experienced dramatic changes (especially in the 2000s) in the starchy R&T supply per capita—from an average of 8 kg/year in 1980-1982 to 29 kg/year in 2007-2009, an increase of 247% (Table A2-15 in Appendix). Cape Verde, which experienced rapid economic growth and has the highest per-capita income in the sub-region, experienced an increase in the supply of almost all major food groups in the study period: per capita supply of fruit by 106%; that of vegetables by 777%; that of meats and offal by 332%; that of milk supply by 69%; that of eggs by 300%; that of sugars and sweeteners by 69% and that of alcoholic beverages by 200%. In contrast, the per capita availability of pulses decreased by 27% and that of fish and seafood declined by 59%. Senegal has also shown a positive trend in the supply of all major food groups (Table A215 in Appendix). In the period of study in Senegal, vegetable supply per capita increased from an average of 17 kg/year in 1980-1982 to 64 kg/year in 2007-2009–an overall increase of 269%; fruit supply remained at less than 20 kg/capita/year, and increased by 29%; the supply of meats and offal per capita increased by 23% per capita; and fish and seafood supply (highest per capita for Senegal in this sub-region) increased by 16%. With the exception of cereals, starchy R&T, alcoholic beverages and fruits, the supply of all other major food groups remained below 20 33 kg/capita/year in Guinea Bissau (Table A2-14 in Appendix). Food supply per capita in the Gambia also did not show any striking changes over time (Table A2-13 in Appendix). Overall, in the Coastal Sahel region, the most noticeable change in the supply of food by major food group has been in the case of starchy R&T in Cape Verde and Senegal. The specific composition of these changes in major starchy staples food groups (cereals and roots and tubers) are investigated in the next sub section. Overall, the analysis of trends in per capita food availability in the ECOWAS states shows the following trends in food supply by major food groups. In the Sahel region, we observe an increase in the supply of starchy R&T (e.g., in Mali, Senegal and Cape Verde). In most countries across all sub regions, we observe an increase in the per capita supply of fruits and vegetables, and also of meats and offal. However, while cereals have been for a long time basic staples in the Sahel and as such most fully reported in official production statistics, agricultural production statistics in underdeveloped low-income countries have been criticized for being deficient in the reporting of figures for crops like cassava, fruits and vegetables as well as livestock (Farnsworth, 1961). Hence, this raises a question of the extent to which the apparent diversification (more starchy staples, more fruits and vegetables) of the diet (in terms of major commodities) over time shown by the FBS reflects real diversification versus just an improvement in the ability of national agricultural statistics to capture non-cereal production (e.g., roots, tubers and horticultural products). 2.5.2.3. Trends in the Availability of Major Starchy Staple Types (kg/capita/year) This sub-section examines the trends in the availability of specific starchy staples for a better understanding of the dynamics of food supply in the region. Disaggregating major starchy staple 34 food groups into specific starchy staples is useful for hypothesizing about possible reasons for any shifts in food supply. For instance, increased per capita supply of starchy R&T could reflect two very different phenomena: (a) the poor shifting towards cheaper sources of calories, such as cassava and sweet potatoes, and (b) the middle class diversifying to a more “European” diet (potatoes—especially French fries). Such analysis is also useful in describing the nature of the diversification and the trend in the relative importance of each starchy staple type in the diet (in terms of specific commodities). For instance, with rising urbanization and growth in per capita incomes, it is worth investigating whether the expected shift to rice (due to urbanization) from coarse grains (e.g., millet and sorghum) is reflected in aggregate per capita cereals supply trends. The analysis of food balance sheet data reveals complex and diverse patterns of substitution amongst different starchy staple types in the different sub-regions. Empirical data reveals that the substitution is not just between rice and wheat and traditional starchy staples (millet and sorghum) as was argued in the 1980s and the 1990s, but also involves other starchy staples types like cassava, yams, sweet potatoes, Irish potatoes and maize. However, the specific pattern of substitution varies across countries and sub-regions. 2.5.2.3.1. Major Starchy Staples Availability in the Non-Coastal Sahel Empirical data on the per capita supply of major starchy staple types shows a growth in per capita supply of rice in Burkina Faso (8 kg/capita), Mali (31 kg/capita) and Niger (6 kg/capita) for the period 1980-85 to 2004-09 (Table A2-16 in Appendix ). Specifically in Mali, while in the 1980s and 1990s millet and sorghum were the most important cereals (in terms of per capita quantities supplied), in the 2000s in Mali rice replaced sorghum as the second most important cereal. This switch from sorghum to rice in Mali is not surprising given Mali’s efforts towards 35 self-sufficiency in rice supply; rice production in Mali in the 2000s has more than doubled its level in the 1990s, and the supply of rice per capita has shown dramatic increases in the 2000s. Maize supply per capita in the Non-Coastal Sahel also showed large absolute increases in the period 1980-85 to 2004-09 inBurkina Faso (32 kg/year) and Mali (17 kg/year). Still in Mali, sweet potatoes availability increased in absolute terms by 14 kg/year, while that of Irish potatoes increased by 6 kg/year, in the study period. The growth in sweet potato availability in Mali may reflect the poor shifting to cheaper sources of calories. Thus, from this breakdown in the supply of major starchy staple types in Mali, it is clear that the recent growth in the supply of starchy R&T seen in the previous sub-section is mostly driven by increases in the supply of sweet potatoes and to a lesser extent yams and Irish potatoes. Per capita availability of wheat, sorghum, cassava and yams were generally below 5 kg/year (Figure 2.5). In Niger, with the exception of millet, rice, and maize, there was an absolute decrease in per capita availability of all major starchy staple types in Niger. This stagnating trend in per capita food supply most likely reflects the impact of economic stagnation in Niger. 36 Figure 2-5. Major Starchy Staples Availability - Mali (kg/capita/year) 80 70 Wheat kg/capita/year 60 Rice (Milled Equivalent) 50 Maize 40 Millet Sorghum 30 Potatoes 20 Sweet Potatoes 10 Yams Cassava 0 Source: Author’s computation using FAO’s Food Balance Sheet data. 2.5.2.3.2. Major Starchy Staples Availability in the Coastal Sahel Data for the Coastal Sahel (Table A2-17 Appendix) also reveals diverse patterns of substitution amongst different starchy staple types. In Cape Verde, in spite of the dominant position of maize in starchy staples availability in the 1980s and the 1990s, maize supply per capita decreased drastically over time, while rice supply has grown to replace maize as the dominant starchy staple type since the mid-2000s. In the period 1980-85 through to 2004-2009, there was an absolute increase in per capita rice supply of 60 kg/year, while that of maize declined by 31 kg/year (Figure 2.6). An increase in rice supply implies increases in imports because most of it is 37 imported14 . Alongside the big increase in per capita rice availability in Cape Verde has been a rapid growth in the supply of Irish potatoes, whereby the per capita supply of Irish potatoes rose from an average of 11 kg/year in the period 1980-1985 to an average of 29 kg/year in 2004-2009. Figure 2-6. Major Starchy Staples Availability - Cape Verde (kg/capita/year) 100 90 Wheat kg/capita/year 80 70 60 Rice (Milled Equivalent) 50 Maize 40 30 20 Cassava Potatoes 10 0 Sweet Potatoes Source: Author’s computation using FAO’s Food Balance Sheet data. In Senegal, rice was the dominant starchy staple type (greater than 55 kg/capita/year) throughout the study period. However, per capita maize availability increased (by 13kg/year) more than that of rice (5 kg/year) over the 30-year period (Figure 2-7). Senegal also experienced a very sharp decline in millet and sorghum availability per capita. This reflects a major shift in the composition of the average diet, linked possibly to urbanization. Furthermore, wheat availability per capita also increased in Senegal by 12 kg/year during the study period. Increases FAO’s FBS reveal rice production data for Cape Verde of less than 1000 tons throughout the period 1980-2009, while rice imports increased from an average of 10,000 tons in the period 1980-84 to 46,000 tons in 2005-09. 38 14 in wheat supply, like that of rice, imply an increase in imports since most of it is imported15. Still in Senegal, cassava availability per capita experienced the largest absolute increase (14 kg/year) amongst all other starchy staples in the study period. Guinea Bissau also showed the most absolute increase in the availability of cassava per capita (24 kg/year) in the study period. Figure 2-7. Major Starchy Staples Availability - Senegal (kg/capita/year) 80 70 kg/capita/year 60 Wheat 50 Rice (Milled Equivalent) 40 Maize 30 Millet 20 Sorghum Cassava 10 Potatoes 0 2007-09 2004-06 2001-03 1998-00 1995-97 1992-94 1989-91 1986-88 1983-85 1980-82 Source: Author’s computation using FAO’s Food Balance Sheet data. Gossen (2002) found that in Rwanda income growth led to higher Irish potato consumption, both in rural and urban areas (short-term income elasticity: rural 1.45 and urban 1.25). The income elasticity of Irish potatoes demand in the Coastal Sahel region also appears to be high. The growth in the supply of Irish potatoes in Cape Verde could be the result of the rapid economic growth experienced in the last 20 years (Table 2-2). Another possible explanation for 15 FAO’s FBS shows no data (or less than 1000 tons/year) of wheat production in Senegal. 39 the growth in the supply of Irish potatoes in Cape Verde is changes in lifestyle–i.e., growth in the consumption of more potato chips (French fries) as people adopt a more Western diet. While the growth in the supply of Irish potatoes could be the result of the westernization of diets and economic growth, the rapid growth in the supply of cassava (Senegal and Guinea Bissau), and to a lesser extent sweet potatoes (Senegal) may represent a shift of the poor to cheaper sources of calories. Also from empirical data, millet appears to be replacing rice in terms of per capita availability in the Gambia. The absolute change in per capita availability was plus 27 kg/year for millet and minus 34 kg/year for rice in the period 1980-85 through to 2004-09. However, it is worth pointing out that prior to the CFA franc devaluation, The Gambia had a large reexportation trade of imported rice to Senegal. The drastic decline in per capita rice availability may just reflect the decline in those largely unrecorded previous re-exportations. 2.5.2.3.3. Major Starchy Staples Availability in the Coastal Non-Sahel Empirical data on the per capita supply of major starchy staple types in the Coastal non-Sahel region reveals remarkable increases in the supply of starchy roots and tubers and to a lesser extent cereals (Table A2-18 Appendix). Ghana for example, experienced an absolute increase in per capita availability of cassava of 86 kg/year, while that of yams increased by 67 kg/year. Nigeria also experienced the largest absolute increases in per capita availability with cassava (36 kg/year) and with yams (57 kg/year). Per capita availability of sweet potatoes also increased in Nigeria by 14 kg/year and that of Irish potatoes by 4 kg/year in the study period. In Benin, per capita availability increased the most for yams (56 kg/year) and cassava (25 kg/year). In Guinea 40 and Sierra Leone also, cassava availability per capita increased by 13 kg/year and 36 kg/year respectively in the period 1980-85 through to 2004-09. The increases in the annual per capita supply of specific cereals for Ghana were as follows: rice, 19 kg; wheat, 8 kg; and maize, 6 kg. In Nigeria, the increases in annual per capita availability over the study period were maize, 17 kg; wheat, 4 kg; rice, 7 kg; millet,16 10 kg and sorghum, 6 kg. Benin also experienced an increase in per capita availability of rice (22 kg/year) in the study period. However, given the importance of unrecorded trade between Benin and Nigeria, it is possible that some of the increase in recorded per capita rice availability in Benin actually represented rice transshipped into Nigeria. Maize has over the years maintained its position as the dominant cereal type in Benin. However, per capita maize consumption increased only by 3 kg/year in the period 1980-85 through to 2004-09. Rice availability per capita also increased by 27 kg/year in Guinea in the period 1980-85 through to 2004-09. Contrary to the increase in rice supply in the other countries in this sub-region, rice supply per capita decreased by 7 kg/year in Sierra Leone and by 48 kg/year in Liberia during the study period. For Sierra Leone, the growth in per capita availability of cassava and the decline in rice availability per capita reflect some degree of substitution of cassava for rice, since both crops have been over time major starchy staples in Sierra Leone. For Liberia, following a period of low and relatively stable supply of wheat in the 1980s, per capita wheat supply jumped from an average of 9 kg/capita/year in the period 1992-1994 to 52 kg/capita/year in the period 1995- 16 Nigeria has the largest apparent per capita supply of millet in the Coastal Non-Sahel. This is not surprising because Nigeria is the only one of these countries that also has a large Sudano-Sahelian zone, which is the major area where millet is produced. 41 1997. This corresponded to the period when the first Liberian civil war ended. The spike in wheat supplies most likely reflects an influx of imported wheat to substitute for domestic rice production that had been decimated by the civil war. Overall, in the period 1980-85 through to 2004-09, per capita availability of wheat increased in Liberia by 19 kg/year. In Cote d’Ivoire, with the exception of millet, sweet potatoes and yams, per capita availability dropped for all other major starchy staples in the period 1980-85 through to 2004-09. In Togo, the largest increases in per capita availability were seen with rice (13 kg/year) and maize (24 kg/year. Figures 2-8 and 2-9 shows the trends in major starchy staples supply in Ghana and Nigeria. kg/capita/year Figure 2-8. Major Starchy Staples Availability - Ghana (kg/capita/year) 250 Wheat 200 Rice (Milled Equivalent) Maize 150 Millet Sorghum 100 Cassava 50 Yams Roots, Other 0 2007-09 2004-06 2001-03 1998-00 1995-97 1992-94 1989-91 1986-88 1983-85 1980-82 Source: Author’s computation using FAO’s Food Balance Sheet data. 42 kg/capita/year Figure 2-9. Major Starchy Staples Availability - Nigeria (kg/capita/year) Wheat 180 160 140 120 100 80 60 40 20 0 Rice (Milled Equivalent) Maize Millet Sorghum Cassava Sweet Potatoes 2007-09 2004-06 2001-03 1998-00 1995-97 1992-94 1989-91 1986-88 1983-85 1980-82 Yams Potaotes Source: Author’s computation using FAO’s Food Balance Sheet data. 2.5.2.4. Trends in Per Capita Macronutrient Availability This section examines the trends in macronutrient (fats and protein) in the ECOWAS region. To investigate changes in the quality of food supply over time, the section further breaks down for each country in the region, protein supply by source–animal (e.g., meats) and plant sources of protein (e.g., pulses). Protein quality varies depending on the balance of essential amino acids within a given food.17 Animal protein generally has a better amino acid balance than plant protein18, although that generalization has several exceptions. For instance, grain legumes, have a concentration of protein that is at least three times that of maize (the most common consumed staple in Sub-Saharan Africa) and grain legumes contain most essential amino acids ( de Jager, 17 18 http://www.hsph.harvard.edu/nutritionsource/protein-full-story/ http://www.hsph.harvard.edu/nutritionsource/protein-full-story/ 43 2013). Grain legumes (beans, pulses, and oilseeds) are often called ‘poor people’s meat’ because of their high protein content and affordability. In addition, the amino acid balance of grain legume protein complements that of cereals when eaten together, greatly improving the protein quality of the combined food19. Thus, by appropriate mixing plant sources (e.g., maize and beans), one can obtain a mixture of amino acids similar to that available in many animal proteins. Diaz-Bonilla et al. (2000) suggest that the availability of animal proteins is more directly correlated with measures of nutritional security than is the availability of total proteins. With increases in per capita incomes over time, one would expect an increase in the consumption of animal proteins (essentially from meats, eggs, dairy products, and related products). This section goes further to disaggregate total animal protein supply by type of product in order to identify the principal sources of animal protein and shifts in their absolute and relative contributions, as well as determine the trends in the availability of frozen chicken, whose imports have reputedly soared in certain countries over the past 10 years. Plant protein is further differentiated into pulse (beans and dry peas–-high quality protein) and other plant sources (generally cereals and of lower quality). 2.5.2.4.1. Analysis of Protein Supply 2.5.2.4.1.1. Trend in Total Daily Protein Availability Per Capita The analysis of protein supply shows an overall increase in per capita protein supply for almost all 15 countries between 1998-2000 and 2007-2009. However, we observe different patterns across the 15 ECOWAS countries. Cape Verde (Coastal Sahel), Ghana and Nigeria (Coastal Non-Sahel) http://www.cgiar.org/our-research/cgiar-research-programs/cgiar-research-program-on-grainlegumes/ 44 19 have shown remarkable growth in daily protein availability per capita. Mali (Non-Coastal Sahel) has also shown a steady increase in the supply of proteins per capita per day in the study period. Figures 2-10, 2-11, and 2-12 show the trends in total daily protein supply in the Non-Coastal Sahel, Coastal Sahel, and Coastal Non-Sahel sub regions. Figure 2-10. Protein Availability (g/capita/day) Non-Coastal Sahel 90 1980-82 g/capita/day 80 70 1983-85 60 1986-88 50 1989-91 40 1992-94 30 1995-97 20 1998-00 10 2001-03 0 BURKINA FASO MALI NIGER 2004-06 Source: Author’s computation using FAO’s Food Balance Sheet data. Figure 2-11. Protein Availability (g/capita/day)-Coastal Sahel 80 1980-82 70 1983-85 g/capita/day 60 1986-88 50 1989-91 40 1992-94 30 1995-97 20 1998-00 10 2001-03 0 2004-06 CAPE VERDE GAMBIA GUINEA BISSAU SENEGAL Source: Author’s computation using FAO’s Food Balance Sheet data. 45 2007-09 Figure 2-12. Protein Availability (g/capita/day)-Coastal Non-Sahel 70 60 1980-82 g/capita/day 50 1983-85 40 1986-88 30 1989-91 1992-94 20 1995-97 10 1998-00 2001-03 0 TOGO SIERRA LEONE NIGERIA LIBERIA GUINEA GHANA COTE D'IVOIRE BENIN 2004-06 2007-09 Source: Author’s computation using FAO’s Food Balance Sheet data. 2.5.2.4.1.2. Daily Protein Supply by Source-Animal versus Plant Protein The analysis if daily protein supply per capita by source reveals that overall, plant protein is the principal source of protein for almost all countries in the region (with the exception of Cape Verde), and the growth in daily protein supply per capita was mostly driven by growth in plant protein in the period 1980-85 through to 2004-09. Animal protein supply has been increasing for most countries in the region. However, growth in the supply of animal protein has been remarkable in countries that have experienced rapid economic growth over time like Ghana and Cape Verde. Countries with modest economic growth over time like Mali have also shown modest changes in the supply of animal protein over time. Countries that have been through civil 46 disruption like Liberia and Sierra Leone also showed significant declines in total protein and animal protein supply during periods of war. Specifically, in the Non-Coastal Sahel (Table A2-19 in Appendix), the absolute contribution of animal protein to total daily protein supply in Burkina Faso is lower (less than an average of 10 g/capita/day) than that of Mali and Niger. However, Burkina Faso also exhibited the largest percentage growth in animal protein supply (43%) between 1980-85 and 2004-09, while animal protein supply in Mali and Niger during the same period grew by 16% and 10% respectively. In all three non-Coastal Sahel countries, growth in plant protein accounted for over 85% of the change in total protein supply in the period 1980-85 through to 2004-09. This increase largely reflects the substantial increase in cereal availability in these countries that was described earlier. Figure 2-13 is a graph of animal protein supply in the Non-Coastal Sahel subregion. Figure 2-13. Animal Protein Availability (g/capita/day) Non-Coastal Sahel 25 1980-82 20 1983-85 g/capita/day 1986-88 1989-91 15 1992-94 1995-97 10 1998-00 2001-03 5 2004-06 2007-09 0 Burkina Faso Mali Niger Source: Author’s computation using FAO’s Food Balance Sheet data 47 In the Coastal Sahel a breakdown of per capita protein supply by source (Table A2-20 in Appendix) reveals that the supply of animal protein has not only been the highest for Cape Verde, but has also shown significant growth (+54%) between 1980-85 and 2004-09. The supply of animal protein has been greater than 20 g/capita/day since 1992-1994, and the share of animal protein in total daily protein supply in Cape Verde has been greater than 40% and increasing since 2000. In Cape Verde, animal protein growth accounts for about 263% of the growth in total daily protein supply experienced in the study period. The high per capita consumption of animal protein in Cape Verde and the corresponding growth over time is not surprising giving the rapid economic growth experienced by the country in the past two decades. Animal protein supply in Senegal has been between an average of 15-20 g/capita/day since the 1980s and increased by 9.7%, while plant protein declined by 14% in the period 1980-85 through to 2004-09. Figure 214 illustrates trends in per capita animal protein supply in these two countries as well as in The Gambia and Guinea Bissau. Figure 2-14. Animal Protein Availability (g/capita/day) Coastal Sahel 35 1980-82 30 g/capita/day 1983-85 25 1986-88 20 1989-91 1992-94 15 1995-97 10 1998-00 2001-03 5 2004-06 2007-09 0 Cape Verde Gambia Guinea Bissau Senegal Source: Author’s computation using FAO’s Food Balance Sheet data. 48 In the Coastal Non-Sahel, a breakdown of daily protein supply by source (Table A2-21 in Appendix) reveals remarkable growth in Ghana with respect to the per capita supply of animal protein. Animal protein supply per person increased in Ghana by 32% between 1980-85 and 2004-09; this growth is likely explained by the strong economic growth experienced by Ghana in the last 15 years. In spite of being amongst the leaders in total daily protein supply per capita in the Coastal Non-Sahel, the supply of animal protein in Nigeria is relatively low–it has been less than an average of 10 g/capita/day since the period 1983-1985. Thus, plant protein largely dominates animal protein in Nigeria, and per capita plant protein increased by 66% while animal protein per person decreased by 11% in the study period. Thus, unlike in Ghana and Cape Verde, the growth in daily protein supply in Nigeria has been driven mainly by increases in cereals availability and, to a lesser degree, pulse availability. In contrast, in spite of the almost constant level of total daily protein supply in Guinea, the supply of animal protein has been increasing over time. Animal protein supply increased by 42% in Guinea in the study period. Prior to the 1990s, Cote d’Ivoire sustained the largest supply per capita of animal protein in the sub-region. However, this supply dropped in the 1990s and the early 2000s. Since the mid2000s, animal protein supply in Cote d’Ivoire has been between 11 and 12 g/capita/day, with an overall drop of 27% in the study period. Liberia, which also suffered a civil war as did Cote d’Ivoire, likewise exhibited a sharp decline in animal protein supply per person–from slightly over an average of 10 g/capita/day in the 1980s, to less than 8 g/capita/day in the 1990s, and finally to less than 6 g/capita/day in the 2000s. Overall, animal protein supply per capita in Liberia declined by 48% in the study period. Animal protein supply per capita in Togo was less than an average of 8 g/capita/day and declined by 7% in the study period. In contrast, animal protein supply per person has been increasing in Sierra Leone since 2001-2003 (the end of the 49 country’s civil war), with an overall increase of 28% in the study period. With the exception of Cote d’Ivoire, Guinea, and Liberia in the Coastal Non-Sahel region, more than 75% of the change in total daily supply of protein per person is accounted for by the growth in plant protein supply. Figure 2-15 shows the trend in animal protein availability per capita in the Coastal nonSahel. Figure 2-15. Animal Protein Availability (g/capita/day) Coastal Non-Sahel 20 18 1980-82 16 1983-85 g/capita/day 14 1986-88 12 1989-91 10 1992-94 8 1995-97 6 1998-00 2001-03 4 2004-06 2 2007-09 0 Benin Cote Ghana Guinea Liberia Nigeria Sierra d'Ivoire Leone Togo Source: Author’s computation using FAO’sFood Balance Sheet data 50 2.5.2.4.1.3. Animal Protein by Source Overall, a disaggregation of animal protein by specific source (meats, fish and seafood, eggs, and milk) revealed some interesting trends across all countries in the region. To ensure comparability, the supply of milk reported in FAOSTAT is converted20 to its dry milk equivalent given that fluid milk has a high water content. Particularly, the rate of growth in poultry meat supply per capita has been quite large for most countries in the region–from 45% in Togo to 1246% in Cape Verde, in the period 1980-85 through to 2004-09. In Benin, for instance, poultry meat supply per capita and milk increased at the expense of all other sources of animal protein, indicating some level of substitution. However, in the Coastal Non-Sahel, fish and seafood remains the most important animal protein source in spite of the increase in poultry meat availability. In Guinea and Sierra Leone, fish and seafood supply per capita grew in the study period. Fish and seafood supply per capita also increased in Niger and Mali (Non-Coastal Sahel), and Senegal and the Gambia (Coastal Sahel). In the Gambia, poultry meat, fish, and seafood and, to a small extent, eggs are substituting for all other sources of animal protein. Empirical data for the Non-Coastal Sahel reveals that over time, beef, mutton, and goat meat have been the major sources of meat in the Non-Coastal Sahel region. In Burkina Faso (Table 2-3), in the study period, per capita supply of beef increased by 4 kg/year (109%); that of mutton and goat meat increased by 1 kg/year (35%); that of pig meat by 2 kg/year (about 357%, albeit from a very low base); that of poultry meat by 49%; that of fish and 20 Conversion factor is 10%, i.e., dry milk equals fluid milk divided by 10. 51 seafood by 15%; and that of eggs increased by 1 kg/capita (about 100%). Milk supply in dry milk equivalent decreased by 1 kg (29%) in Burkina Faso in the study period. In Mali (Table 2-4), poultry meat supply grew the most in percentage terms (50%) in the study period but still remains well below the supply of beef, mutton and goat meat. Fish and seafood supply is largest for Mali in the Non-Coastal Sahel region, and has been fairly stable over time. Milk supply in Mali increased by 1 kg (13%) in the period 1980-85 through to 200409. Egg supply per capita was below 1 kg/year in the study period. In Niger (Table 2-5), beef supply per capita experienced the largest absolute increase–5 kg/year (56%) in the period 198085 through to 2004-09. Per capita consumption of fish and seafood also grew by 2 kg/year (218%), while that of poultry meat dropped by 40%. 52 Table 2-3. Three-Year Averages of Animal Protein Supply (kg/capita) in Non-Coastal Sahel- Burkina Faso 1980 to 1982 1983 to 1985 1986 to 1988 1989 to 1991 1992 to 1994 1995 to 1997 1998 to 2000 2001 to 2003 2004 to 2006 2007 to 2009 Bovine Meat Mutton & Goat Meat Pigmeat 3.2 3.9 4.4 5.7 6.4 6.8 7.1 7.4 7.7 7.2 % change 1980-85 to 2004-09 109.30% 2.1 2.6 2.8 3.2 3.3 3.3 3.3 3.3 3.2 3.1 34.80% 1.2% 0.4 0.6 0.7 0.8 1.1 1.3 1.6 2 2.4 2.2 356.70% 6.3% Poultry Meat 1.4 1.6 2 2.2 2.2 2.2 2.2 2.3 2.2 2.2 49.40% 1.5% Meat, Other 0.9 0.9 0.9 0.8 0.7 0.7 0.6 0.6 0.6 0.6 -34.50% -1.6% Fish & Seafood 2 2 2 2 2 2 2 2 2 2 2 2 2 2 100% 2.8% 1.8 1.6 1.7 1.7 -29% -1.4% 1 1 1 2 3 3 Eggs Milk - dry 2.6 2.2 2.3 1.6 1.6 1.7 equivalent Source: Author's calculations using FAO’s Food Balance Sheet data. 53 CAGR 1980/85 to 2005/09 3.0% 0.6% Table 2-4. Three-Year Averages of Animal Protein Supply (kg/capita) in Non-Coastal Sahel - Mali 1980 to 1982 1983 to 1985 1986 to 1988 1989 to 1991 1992 to 1994 1995 to 1997 1998 to 2000 2001 to 2003 2004 to 2006 2007 to 2009 Bovine Meat 5.8 6.7 7.8 8.3 6.0 6.1 6.6 7.4 8.2 9.0 37% 1.3% Mutton and Goat Meat Pig Meat 6.5 4.7 4.2 4.9 4.3 4.5 4.8 5.1 5.5 6.9 10% 0.4% 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 8% 0.0% Poultry Meat 1.7 2.2 2.8 2.7 2.7 2.6 2.8 2.8 3.1 2.8 50% 1.7% Meat, Other 3.3 2.9 2.7 2.6 2.4 2.4 2.5 2.6 2.9 2.9 -7% -0.3% Fish and Seafood 10.2 7.3 7.1 8.3 7.2 11.3 9.4 9.1 9.0 8.1 -2% 0.0% Eggs 0.6 0.7 0.9 0.8 0.8 0.7 0.6 0.5 0.4 0.5 -37% -1.8% Milk - dry equiv. 5.9 4.7 4.6 5.1 5.1 4.8 5.2 5.2 5.7 6.3 13% 0.5% Source: Author’s computation using FAO’s Food Balance Sheet data. 54 % change 1980-85 to 2004-09 CAGR 1980/85 to 2005/09 Table 2-5. Three-Year Averages of Animal Protein Supply (kg/capita) in Non-Coastal Sahel- Niger 1980 to 1982 1983 to 1985 1986 to 1988 1989 to 1991 1992 to 1994 1995 to 1997 14.1 % change 1980-85 to 2004-09 56.40% CAGR 1980/85 to 2005/09 1.8% Bovine Meat Mutton & Goat Meat Pigmeat 9.1 8.2 6.5 6.9 8 8.8 10.3 11.9 12.9 9.7 6.7 6.5 6.2 5.7 5.7 5.9 5.7 6.2 6.5 -22.60% -1.0% 0.2 0.2 0.2 0.2 0.2 0.1 0.1 0.1 0.1 0.1 -50.00% -2.7% Poultry Meat 1.4 1.3 1.2 1.2 1.1 1.1 1 1 0.9 0.7 -40.00% -2.1% Meat, Other 3 2.5 2.7 3 3.4 3.1 3 3.1 3.3 3.2 18.20% 0.7% Fish & Seafood 1 0 0 1 0 1 1 1 3 3 217.86% 4.7% 0.5 0.4 0.4 0.3 -46% -2.4% 4.5 4.8 4.9 5.9 -1% 0.0% 0.6 0.6 0.6 0.6 0.5 0.5 Eggs Milk - dry 5.7 5.2 4.2 4 4 4.3 equivalent Source: Author's calculations using FAO’s Food Balance Sheet data 55 1998 to 2000 2001 to 2003 2004 to 2006 2007 to 2009 In the Coastal Sahel (Table 2-6) there was huge growth in the supply of poultry meat in the period 1980-85 and 2004-09. Poultry meat supply per capita increased by 1,246% in Cape Verde; 455% in The Gambia; 256% in Guinea Bissau; and 101% in Senegal in the study period. Pig meat has been the dominant source of meat over time in Cape Verde, and its supply per person also increased by about 290% in the study period. Unlike pig meat, most of the increase in Cape Verde’s poultry meat was imported. Poultry meat supply from imports increased from less than 1,000 tons prior to 2000 to an average of 8,000 tons in the period 2007-09. In spite of the high per capita availability of fish and seafood in Cape Verde in the early and mid-1980s, per capita availability dropped by 59% in the study period as chicken apparently substituted for fish in consumption. Per capita supply of eggs also increased by 3 kg (an increase of 300%) while that dry milk also increased by about 5 kg (an increase of about 69%) in Cape Verde in the study period. In Senegal and The Gambia, beef dominated in meat supply over time. However, its per capita supply declined over time in both countries. Pig meat is the dominant source of meat in Guinea Bissau (in spite of a 14% decline in per capita supply over time). The fish and seafood supply in Senegal grew from an average of 22 kg/person/year in the period 1980-85 to 25 kg/person/year. 56 Table 2-6. Three-Year Averages of Animal Protein Supply (kg/capita) in Coastal Sahel 1980 to 1982 Bovine Meat Mutton and Goat Meat Pig Meat Poultry Meat Meat, Other Fish and Seafood Eggs Milk - dry equiv. Bovine Meat Mutton and Goat Meat Pig Meat Poultry Meat Meat, Other Fish and Seafood Eggs Milk - dry equiv 1983 to 1985 1986 to 1988 1989 to 1991 1992 to 1994 1.2 1.0 1.2 0.9 1.6 1.1 1.9 1.2 3.9 1.3 4.8 1.0 0.0 34.1 1 6.5 5.7 1.1 0.0 29.1 1 7.2 8.9 1.4 0.0 14.9 1 6.5 10.7 1.5 0.0 16.8 1 5.9 17.8 1.9 0.0 14.0 4 8 6.1 1.9 6.0 2.0 6.2 2.6 5.9 2.7 0.7 1.7 1.3 22.8 1 3.6 0.7 1.6 1.3 21.4 1 4.4 0.5 2.1 1.4 24.1 1 4.3 0.4 2.0 1.5 26.3 1 3.9 1995 to 1997 1998 to 2000 Cape Verde 3.4 1.7 1.1 1.2 2001 to 2003 2004 to 2006 2007 to 2009 % change 1980/85 to 2004/09 CAGR 1980/85 to 2005/09 1.7 1.1 2.0 1.5 3.0 1.9 113% 84% 3.0% 2.4% 18.3 2.8 0.2 19.9 5 8.2 18.8 7.1 0.2 18.6 4 8.7 19.4 12.5 0.2 14.3 4 10.7 21.6 16.7 0.1 11.6 4 12.4 290% 1246% -59% 300% 69% 5.6% 11.1% n.d. -3.5% 5.7% 2.1% 5.4 2.7 15.1 1.5 0.0 18.3 5 8.3 Senegal 4.9 2.7 4.7 2.5 4.5 2.4 5.1 2.6 6.4 2.9 -5% 41% -0.2% 1.4% 0.5 2.0 1.5 34.3 1 4.2 0.5 2.0 1.3 30.7 1 2.9 0.7 2.3 1.3 29.8 1 2.7 1.0 3.1 1.3 28.3 2 2.3 0.9 3.3 1.2 26.5 2 2.9 0.9 3.3 1.3 24.2 2 3.2 34% 101% -4% 15% 100% -24% 1.0% 2.8% -0.2% 0.6% 2.8% -1.1% 57 Table 2-6. (cont’d) 1980 to 1982 Bovine Meat Mutton & Goat Meat Pigmeat Poultry Meat Meat, Other Fish, Seafood Eggs Milk - dry equiv. 1983 to 1985 1986 to 1988 1989 to 1991 1992 to 1994 2001 to 2003 2004 to 2006 2007 to 2009 % change 1980/85 to 2004/09 CAGR 1980/85 to 2005/09 2.4 3 2.5 -43% -2.3% 0.6 0.8 1 1 -37% -1.9% 0.4 0.3 0.9 1.5 0.9 0.8 24 23 1 1 1.7 2.4 Guinea Bissau 3.9 3.8 3.9 0.3 1.2 0.7 29 1 2.8 0.4 4.4 0.7 24 2 2.4 0.5 3.4 1 28 2 3 -24% 455% -43% 58% 100% -0.8% 7.1% -2.2% 1.8% 2.8% -0.4% 3.6 3.6 3.9 32% 1.1% 1.2 1.2 1.2 1.4 18% 0.7% 8.3 1.1 0 4 0.6 1.5 8 1.4 0 2 0.7 1.5 7.9 1.5 0 2 0.7 1.5 8.4 1.7 0 1 0.7 1.6 -14% 256% -100% -40% 110% -6% -0.6% 5.2% n.d. -2.0% 3.0% -0.2% 5.3 4.5 5.2 5.2 4 1.6 1.6 1.5 1.2 0.9 0.6 0.7 1.6 16 1 2.5 0.5 0.7 1.4 17 1 3.4 0.5 0.8 1.3 16 1 2.8 0.6 0.9 1.1 22 1 1.6 0.5 1.1 1 18 1 1.8 1995 to 1997 1998 to 2000 Gambia 3.2 2.9 0.7 Bovine Meat 2.7 3 3 3.5 Mutton & Goat 1.1 1.1 1.1 1.1 1.2 1.2 Meat Pigmeat 9.4 9.4 9.3 8.8 8.7 8.5 Poultry Meat 0.4 0.5 0.6 0.7 0.8 0.8 Meat, Other 0 0 0 0 0 0 Fish, Seafood 3 2 4 4 5 5 Eggs 0.3 0.4 0.4 0.4 0.4 0.5 Milk - dry equiv. 1.6 1.7 2.1 2 2.1 1.7 Source: Author's calculations using FAO’s Food Balance Sheet data. 58 In the Coastal Non-Sahel, Table 2-7 reveals that fish and seafood remain by far the dominant source of animal protein (in spite of the growth in poultry meat consumption). Among meats, poultry has been the dominant meat type in Benin over time. Poultry meat supply per capita increased by 115% between 1980-85 and 2004-09, while the supply of all other types of meats declined in the same period. It is important to note that some of this apparent increase in per capita chicken consumption in Benin may reflect chicken that was clandestinely exported to Nigeria, which had a ban on frozen chicken import during some of this period. While fish and seafood have been dominant sources of animal protein in Benin, per capita supply has been declining over time–from an average of 11 kg/capita/year in 1980-85 to an average of 8.5 kg/capita/year in 2004-09. Egg supply per person per year declined by 1 kg (50%) in the study period, and annual milk supply per capita remained around an average of 1 kg throughout the period of study. In Cote d’Ivoire, the supply per capita of all meat types declined over time, and the largest percentage decline (62%) was for beef and milk. In Ghana, poultry meat supply per capita increased by 570%, while that of fish and seafood increased by 38% in the study period. Fish and seafood supply per capita is largest for Ghana (mostly greater than 25 kg/capita/year) in the Coastal Non-Sahel. Milk supply per person in Ghana increased from an average of 4 kg in the beginning of the period to an average of 8 kg at the end of the period. Poultry meat supply per person in Nigeria dropped by 8% and that of fish and seafood dropped by 10% in the study period. Guinea, Liberia, Sierra Leone, and Togo experienced increases in poultry meat supply per capita of 190%, 168%, 63%, and 45% respectively. Guinea and Sierra Leone also experienced increases in fish and seafood supply per capita of 45% and 36% respectively. 59 Table 2-7. Three-Year Averages of Meat Supply (kg/capita) in Coastal Non-Sahel 1980 to 1982 1983 to 1985 1986 to 1988 1989 to 1991 1992 to 1994 1995 to 1997 Benin 2.8 1998 to 2000 2001 to 2003 2004 to 2006 2007 to 2009 % change 1980/85 to 2004/09 CAGR 1980/85 to 2005/09 2.9 2.8 2.8 2.9 -20% -0.9% 1 0.9 0.9 0.9 -49% -2.6% 0.6 10 2.2 9 1 1.1 0.6 8.5 0.8 9 1 1 0.7 13.6 0.8 8 1 0.8 -57% 115% -50% -23% -50% -3.3% 3.1% -2.6% -1.0% -2.7% 0.5% 1.9 2.1 2.1 -62% -3.8% Bovine Meat Mutton & Goat Meat Pigmeat Poultry Meat Meat, Other Fish, Seafood Eggs Milk - dry equiv 3.5 3.6 3.4 3.4 4.1 1.6 1.9 1.3 1.2 1 1.5 4.1 1.6 12 2 0.8 1.5 6.2 1.5 10 2 0.8 1.5 4.3 1.4 11 2 0.8 1.1 3.2 1.3 9 1 0.6 1.2 4.7 1.2 10 1 0.6 Bovine Meat Mutton & Goat Meat Pigmeat Poultry Meat Meat, Other Fish, Seafood Eggs Milk - dry equiv 5.8 5.2 4.7 5.3 4 1.2 1.1 0.9 0.8 0.7 0.7 0.6 0.6 0.7 0.6 -44% -2.3% 1.1 2.4 10.2 18 1 2.1 0.9 2.2 9.8 16 1 1.8 0.9 2.5 9.3 20 1 2.1 0.9 2.1 9 18 1 1.4 0.8 1.8 8.2 14 1 1.3 0.6 1.6 7.4 13 1 0.9 0.4 1.4 7.1 14 2 0.7 0.4 1.6 7.4 14 2 0.7 0.7 1.6 7.6 14 1 0.8 0.8 1.3 8.2 13 1 0.7 -23% -38% -21% -21% 0% -1.1% -1.8% -0.9% -0.9% 0.0% -3.7% 1.1 1.2 0.5 4.9 7.8 1.1 0.9 10 8 1 1 0.8 1.2 Cote d’Ivoire 2.7 2.4 60 Table 2-7. (cont’d) 1980 to 1982 1983 to 1985 1986 to 1988 1989 to 1991 1992 to 1994 1995 to 1997 1998 to 2000 2001 to 2003 2004 to 2006 2007 to 2009 % change 1980/85 to 2004/09 CAGR 1980/85 to 2005/09 1.4 1.3 1.4 1.7 -7% -0.4% Bovine Meat Mutton & Goat Meat Pigmeat Poultry Meat Meat, Other Fish, Seafood Eggs Milk - dry equiv 1.6 1.8 1.6 2.1 2.7 Ghana 1.6 0.9 0.7 0.7 0.7 0.7 0.7 0.9 1.1 1.2 1.3 56% 1.8% 0.8 0.8 6.7 21 1 0.2 0.7 0.5 7.3 21 0 0.5 0.8 0.5 6.5 26 0 0.4 0.9 1 6.1 25 1 0.4 0.7 1.1 5.6 24 1 0.3 0.7 1.7 5 31 1 0.5 0.7 2.7 4.8 25 1 0.7 0.7 3.7 4.6 28 1 0.8 0.9 5.2 4.5 29 1 0.8 9% 570% -35% 36% 100% 0.3% 8.0% -1.7% 1.2% 2.8% 3.4% Bovine Meat Mutton & Goat Meat Pigmeat Poultry Meat Meat, Other Fish, Seafood Eggs Milk - dry equiv 2.6 2.7 2.1 2.7 3.2 0.8 1.2 5.3 28 1 0.2 Guinea 3.7 3.8 4.1 4.6 5.1 81% 2.4% 0.5 0.6 0.5 0.6 0.6 0.8 0.9 1 1.2 1.5 150% 3.7% 0.4 0.4 0.8 7 1 1 0.3 0.3 0.8 8 1 1.2 0.2 0.4 0.7 8 1 1.1 0.3 0.4 0.7 9 1 1 0.3 0.6 0.7 11 1 1.2 0.2 0.5 0.7 11 1 1.2 0.2 0.6 0.6 12 1 1.3 0.2 0.6 0.6 13 2 1.2 0.2 0.9 0.6 11 2 1.3 0.2 1.2 0.5 10 2 1.4 -38% 190.90% -29.20% 40% 100% -2.2% 4.5% -1.5% 1.4% 2.8% 0.8% 61 Table 2-7. (cont’d) 1980 to 1982 1983 to 1985 1986 to 1988 1989 to 1991 1992 to 1994 1995 to 1997 1998 to 2000 2001 to 2003 2004 to 2006 2007 to 2009 % change 1980/85 to 2004/09 CAGR 1980/85 to 2005/09 0.5 0.4 0.3 -73% -5.3% 0.5 0.4 0.4 0.5 -28% -1.1% 1.9 3.4 3.2 6 2 0.3 1.9 3 2.5 4 1 0.2 2.4 4.2 2.2 5 2 0.4 2.6 4.6 2.4 5 2 0.3 21% 168% -65% -64% 33% 0.8% 4.0% -4.1% -4.0% 1.2% -4.6% 2.4 2.2 2 1.9 -62% -3.8% Bovine Meat Mutton & Goat Meat Pigmeat Poultry Meat Meat, Other Fish, Seafood Eggs Milk - dry equiv 1.4 1.3 0.9 0.9 1.7 Liberia 0.7 0.6 0.6 0.6 0.6 0.6 0.7 0.6 2.1 1.5 6.9 13 1 1 2 1.8 6.3 15 2 1.3 2.2 2.4 6.7 15 2 0.8 2.3 2.7 3.6 10 2 0.4 2.3 2.9 3.6 6 2 0.3 Bovine Meat Mutton & Goat Meat Pigmeat Poultry Meat Meat, Other Fish, Seafood Eggs Milk - dry equiv 5 5.2 3 2.2 2.3 1.2 1.4 1.6 1.7 1.8 2.1 2.6 2.8 2.8 2.8 110% 3.1% 0.5 1.8 1.3 16 3 1.5 0.6 1.7 1.2 9 3 0.9 1 1.7 1.1 7 3 0.5 1.1 1.8 1 10 3 0.6 1.1 1.6 1 6 4 0.6 1.2 1.5 0.9 7 3 0.6 1.3 1.4 0.9 7 3 0.5 1.4 1.5 0.9 9 3 0.7 1.4 1.6 0.9 9 3 0.8 1.4 1.6 0.9 13 4 0.8 158% -8% -31% 28% 12% 3.8% -0.4% -1.3% -0.5% 0.6% -1.6% 2.2 3.1 3.6 6 2 0.3 Nigeria 2.5 62 Table 2-7. (cont’d) 1980 to 1982 Bovine Meat Mutton & Goat Meat Pigmeat Poultry Meat Meat, Other Fish, Seafood Eggs Milk - dry equiv 1983 to 1985 1986 to 1988 1989 to 1991 1992 to 1994 1995 to 1997 1998 to 2000 2001 to 2003 2004 to 2006 2007 to 2009 % change 1980/85 to 2004/09 CAGR 1980/85 to 2005/09 1.1 1.3 1.5 -14.30% -0.7% 1.7 1.6 1.4 1.4 Sierra Leone 1.8 1.5 1.4 0.4 0.4 0.3 0.3 0.4 0.3 0.3 0.2 0.4 0.5 16.70% 0.5% 0.6 1.8 0.6 22 1 1.6 0.6 1.8 0.6 17 1 0.9 0.6 2 0.5 14 1 0.9 0.6 2.1 0.5 14 1 0.8 0.6 2.2 0.5 14 1 0.8 0.6 2.3 0.5 14 2 0.5 Togo 1.4 0.6 2.5 0.6 15 2 0.3 0.6 3.4 1.1 18 2 0.4 0.5 2.8 1.8 27 1 0.5 0.6 3 1.8 25 2 0.5 -3% 63% 203% 33% 50% -0.3% 1.9% 4.5% 1.2% 1.6% -3.6% 1.3 1.5 1.5 1.7 95% -1.8% 1.3 1.3 1.3 1.4 50% 1.4% 1.2 2.9 0.8 10 1 0.3 1.3 3.9 0.9 7 1 0.4 1.4 3.7 0.8 7 1 0.6 1.6 5.2 0.9 7 1 0.5 20% 45% 89% -38% 0% 1.0% 3.0% -1.8% -1.6% 2.8% 1.3% Bovine Meat 2 3 3.1 1.6 1.2 Mutton & Goat 0.9 1 1.5 1.7 1.1 1 Meat Pigmeat 1.2 1.1 1.2 1.5 1.5 1 Poultry Meat 2.2 2 3.2 2.4 2.2 2.6 Meat, Other 1.4 1.2 1.2 1.1 1 0.9 Fish, Seafood 11 10 12 12 11 14 Eggs 0 1 1 1 1 1 Milk - dry equiv 0.4 0.4 0.4 0.5 0.4 0.5 Source: Author’s computation using FAO’s Food Balance Sheet data 63 2.5.2.4.1.4. Plant Protein by Source To further examine the quality of protein supplied, plant protein was disaggregated between the portion due to pulses and all other plant sources. Pulses are an important share of plant protein supply in Cape Verde, Niger, and Nigeria. Pulses have accounted for 9% (Burkina Faso) to 57% (Niger) of the change in plant protein supply in the period 1980-85 through to 2004-09. Compared to the Non-Coastal Sahel, and with the exception Cape Verde, pulses contribute less than 10 g/capita/day of protein and have had small shares (less than 10%) in daily plant protein supply in the Coastal Sahel. In the Coastal Non-Sahel sub-region, protein supply from pulses has been less than 10 g/capita/day, and pulses accounted for from 16% (Nigeria) to 257% (Guinea—from a small base) of the growth in plant protein in the period of study. The growth in the share of pulses in daily plant protein supply reflects some degree of diet upgrading. Thus, in spite of the relatively low per capita availability of high quality animal protein in most countries in the region, the positive growth in protein supply from pulses as well as in the share of pulses in daily plant protein supply supports the emergence of pulses as poor people’s meat in the region. Tables 2-8, 2-9, and 2-10 shows the contribution of pulses to daily plant protein supply per capita in the Non-Coastal Sahel, the Coastal Sahel and the Coastal Non-Sahel sub regions, respectively. 64 Table 2-8. The Contribution of Pulses to Plant Protein Supply (g/capita/day) Non-Coastal Sahel 1980 to 1982 1983 to 1985 1986 to 1988 1989 to 1991 1992 to 1994 1995 to 1997 Burkina Faso Plant - Total 46.6 46.8 61.4 64.3 69.9 67.2 Pulses -Total 5.8 5.4 6.9 7.2 7.5 6.7 Pulse Share 13% 11% 11% 11% 11% 10% Mali Plant - Total 31.0 37.3 44.3 44.6 46.8 47.2 Pulses -Total 2.2 2.5 3.2 3.4 6.0 5.5 Pulse Share 7% 7% 7% 8% 13% 12% Niger Plant - Total 47.5 45.2 45.4 43.8 41.7 41.9 Pulses -Total 13.9 10.8 11.4 9.2 8.4 8.4 Pulse Share 29% 24% 25% 21% 20% 20% Source: Author's calculations using FAO’s Food Balance Sheet data 65 1998 to 2000 2001 to 2003 2004 to 2006 2007 to 2009 % of total change 66.1 7.0 11% 69.1 6.8 10% 69.6 7.7 11% 70.7 7.8 11% 9% 49.4 7.5 15% 51.0 6.8 13% 52.3 6.1 12% 52.6 4.5 9% 16% 49.4 14.8 30% 48.4 11.8 24% 51.9 14.5 28% 61.9 22.1 36% 57% % change 1980-85 to 2004-09 -8% 46% 20% Table 2-9. The Contribution of Pulses to Plant Protein Supply (g/capita/day)-Coastal Sahel 1980 to 1982 1983 to 1985 1986 to 1988 1989 to 1991 1992 to 1994 1995 to 1997 Cape Verde Plant- Total 45.1 47.5 55.3 45.0 39.2 36.9 Pulses -Total 7.1 8.4 16.3 9.6 3.9 4.9 Pulse Share 16% 18% 29% 21% 10% 13% Gambia Plant- Total 36.5 39.4 43.3 41.3 38.8 37.2 Pulses -Total 3.1 2.8 2.5 2.2 2.0 1.6 Pulse Share 8% 7% 6% 5% 5% 4% Guinea Bissau Plant- Total 35.6 36.6 36.0 36.5 36.2 35.0 Pulses -Total 1.3 1.3 1.2 1.2 1.1 1.1 Pulse Share 4% 3% 3% 3% 3% 3% Senegal Plant- Total 50.4 49.2 49.4 47.5 42.1 41.3 Pulses -Total 1.9 2.8 3.0 1.4 2.1 2.0 Pulse Share 4% 6% 6% 3% 5% 5% Source: Author's calculations using FAO’s Food Balance Sheet data 66 1998 to 2000 2001 to 2003 2004 to 2006 2007 to 2009 % of total change 39.1 5.6 14% 37.4 4.8 13% 38.6 4.6 12% 41.0 6.5 16% 33% 37.9 1.7 4% 40.0 2.6 7% 39.6 1.3 3% 44.9 1.2 3% -40% 34.4 1.1 3% 34.7 0.9 3% 35.8 0.9 2% 36.6 1.8 5% 38% 42.5 3.1 7% 37.2 1.1 3% 41.3 2.2 5% 43.6 3.5 8% -7% % change 1980-85 to 2004-09 -16% -62% 3% 40% Table 2-10. The Contribution of Pulses to Plant Protein (g/capita/day) Coastal Non-Sahel 1980 to 1982 1983 to 1985 1986 to 1988 1989 to 1991 Plant - Total Pulses -Total Pulse Share 36.4 3.3 9% 36.9 3.7 10% 39.8 4.3 11% 44.7 4.7 11% Plant - Total Pulses -Total Pulse Share 43.2 0.5 1% 40.8 0.4 1% 39.1 0.4 1% 37.7 0.4 1% Plant - Total Pulses -Total Pulse Share 25.9 0.7 3% 28.4 0.5 2% 31.1 0.6 2% 31.3 0.6 2% Plant - Total Pulses -Total Pulse Share 46.2 4.4 10% 46.4 4.4 9% 47.8 4.7 10% 47.9 5.1 11% 1992 to 1994 1995 to 1997 Benin 45.0 46.3 5.2 4.9 12% 11% Cote d'Ivoire 37.1 37.0 0.3 0.5 1% 1% Ghana 36.5 37.6 0.5 0.4 1% 1% Guinea 47.1 45.4 4.5 4.1 10% 9% 67 1998 to 2000 2001 to 2003 2004 to 2006 2007 to 2009 % of total change 47.2 5.6 12% 48.0 5.7 12% 48.8 6.4 13% 51.7 8.9 17% 31% 36.6 1.0 3% 36.8 1.0 3% 37.4 1.2 3% 40.4 1.3 3% -26% 38.6 0.4 1% 40.6 0.3 1% 42.5 0.4 1% 43.3 0.4 1% -1% 44.9 4.0 9% 44.6 3.8 9% 44.8 3.6 8% 47.0 3.3 7% 257% % change 1980-85 to 2004-09 59% 200% -55% -22% Table 2-10. (cont’d) 1980 to 1982 1983 to 1985 1986 to 1988 1989 to 1991 1992 to 1994 1995 to 1997 Liberia Plant- Total 37.6 35.5 36.0 33.6 31.5 34.0 Pulses -Total 0.8 0.8 0.8 1.1 1.8 2.4 Pulse Share 2% 2% 2% 3% 6% 7% Nigeria Plant- - Total 32.3 32.9 38.9 42.9 46.3 49.2 Pulses -Total 2.6 2.3 2.9 4.6 4.8 5.3 Pulse Share 8% 7% 7% 11% 10% 11% Sierra Leone Plant- - Total 33.4 32.2 33.2 33.4 33.8 36.1 Pulses -Total 4.8 4.6 4.6 4.8 4.7 5.5 Pulse Share 14% 14% 14% 14% 14% 15% Togo Plant- - Total 38.6 37.8 35.7 37.8 39.3 41.0 Pulses -Total 4.1 4.7 3.9 2.7 3.8 5.0 Pulse Share 11% 12% 11% 7% 10% 12% Source: Author’s computation using FAO’s Food Balance Sheet data. 68 1998 to 2000 2001 to 2003 2004 to 2006 2007 to 2009 % of total change 33.2 2.6 8% 28.3 1.4 5% 29.2 1.7 6% 31.5 1.5 5% -13% 51.1 5.9 11% 49.8 5.4 11% 52.7 5.6 11% 54.6 6.3 11% 16% 37.0 6.9 19% 38.0 7.5 20% 40.0 7.6 19% 39.5 7.2 18% 39% 40.3 4.3 11% 40.9 4.3 11% 42.2 4.9 12% 45.9 6.1 13% 19% % change 1980-85 to 2004-09 142% 46% 30% 8% 2.5.2.4.2. Analysis of Fat Supply With the exception of Sierra Leone, total fat availability per capita increased for all countries in the period 1980-85 and 2004-09, and has been generally highest for Coastal Sahelian countries. Notwithstanding, the percentage increases in per capita fat supply were largest for non-Coastal Sahelian countries. Figures 2-16 to 2-18 show the trends in daily fat supply (g/capita/day) by subregion. Figure 2-16. Fat Availability (g/capita/day) Non-Coastal Sahel 70 60 1980-82 1983-85 50 g/capita/day 1986-88 1989-91 40 1992-94 1995-97 30 1998-00 20 2001-03 2004-06 10 2007-09 0 BURKINA FASO MALI NIGER Source: Author’s computation using FAO’s Food Balance Sheet data. 69 Figure 2-17. Fat Availability (g/capita/day) Coastal Sahel 90 80 1980-82 g/capita/day 70 1983-85 60 1986-88 50 1989-91 1992-94 40 1995-97 30 1998-00 20 2001-03 10 2004-06 2007-09 0 CAPE VERDE GAMBIA GUINEA BISSAU SENEGAL Source: Author’s computation using FAO’sFood Balance Sheet data. Figure 2-18. Fat Availability (g/capita/day) Coastal Non-Sahel 80 1980-82 g/capita/day 70 20 1995-97 10 1998-00 0 2001-03 TOGO 1992-94 SIERRA LEONE 30 NIGERIA 1989-91 LIBERIA 40 GUINEA 1986-88 GHANA 50 COTE D'IVOIRE 1983-85 BENIN 60 Source: Author’s computation using FAO’s–Food Balance Sheet data 70 2004-06 2007-09 2.5.2.5. Trends in the Share of Macronutrient Group in Daily Per Capita Energy Supply The contribution of various macronutrient groups to total daily per capita energy supply is one indicator of diet quality. This section examines whether the composition of per capita food supply in terms of major macronutrient groups is becoming more balanced, based on the joint FAO/WHO guidelines for various nutrients for a balanced diet—55-75% of total calories from carbohydrates, 15-35% from fats and 10-15% from proteins (Nishida et al. 2004). The analysis reveals that over time, while most countries in ECOWAS-WA have remained close to the upper bound of the daily recommended share of carbohydrates in energy supply, few of these countries deviate from the lower bound of the recommended share of protein and fats in daily energy supply. 2.5.2.5.1. Non-Coastal Sahel Figure 2-19 shows the trends in the share of various macronutrient groups in total daily energy supply per capita in the Non-Coastal Sahel. (See Me-Nsope and Staatz (2013) for the underlying data for this and the other sub-regions.) The share of protein, fats, and carbohydrates in total daily energy supply has not changed much. In particular, the share of protein seems almost constant over time, as minor redistributions takes place between fats and carbohydrates. Nonetheless, since total per capita calorie availability increased markedly for these countries over the study period, the absolute levels of fat and protein consumption also increased substantially. In addition, we saw from the analysis of protein by source in the Non-Coastal Sahel that the contribution of animal protein has been growing since the early 2000s. Thus, in spite of the almost constant share of protein in total daily energy supply, the quality of protein supply has improved to some extent due to the growth in consumption of animal protein. 71 2.5.2.5.2. Coastal Sahel In the Coastal Sahel (Figure 2-20), the share of carbohydrates still remains close to the upper bound of the daily-recommended share. The share of protein has also remained close to its dailyrecommended lower bound (10-15%). The Gambia and Guinea Bissau over time have fallen below the minimum daily protein share in total daily energy supply. As was the case in the Non-Coastal Sahel, just focusing on the share of protein in total daily energy supply obscures the important changes that have taken place (in particular in Cape Verde) in terms of the quality of protein supply. The share of fat in daily energy supply has been much higher in the Coastal Sahel than in the NonCoastal Sahel. 2.5.2.5.3. Coastal Non-Sahel In the Coastal Non-Sahel region, a similar pattern of not much variation in the share of each macronutrient group in daily per capita energy supply is observed (Figure 2-21). However, unlike in the case of the Coastal and Non-Coastal Sahel, the share of protein in daily energy, over time, and for almost all Coastal Non-Sahelian countries, has remained below the recommended daily protein share (10%) in total daily energy supply. With the exception of Sierra Leone, which has shown a slight increase in protein share over time, protein share in all the other countries has been either constant or declining. It is, however, worth noting that while the share of protein in total daily energy supply has not shown much change, the analysis of protein supply in absolute terms as well as of the contribution of animal protein to total protein supply seen earlier revealed not only an increase in the amount of protein supplied over time (Benin, Ghana, Nigeria, Sierra Leone), but also 72 an increase in the quality of protein supply over time (Ghana, Nigeria21 and Sierra Leone). Ghana and Cote d’Ivoire have consistently had higher than the daily-recommended carbohydrate share over time, and this seems not to be changing much. This is not surprising because of the high consumption of starchy roots and tubers in these countries. Guinea, Liberia, and Togo, in contrast, have experienced a decline in the share of carbohydrates towards the upper bound of the recommended daily share. In Nigeria, the increase in the supply of protein from pulses per capita over time offsets the decline in animal protein supply per capita, so that overall, the supply of high quality protein (pulses and animal sources) increased over time. 73 21 Figure 2-19. Daily Caloric Share (%) by Macronutrients - Non-Coastal Sahel 100% 90% 80% 70% 60% 50% 40% 30% 20% 10% Burkina Faso Mali Protein Fat Carbohydrates Source: Author’s computation using FAO’s Food Balance Sheet data 74 1980-82 1983-85 1986-88 1989-91 1992-94 1995-97 1998-00 2001-03 2004-06 2007-09 1980-82 1983-85 1986-88 1989-91 1992-94 1995-97 1998-00 2001-03 2004-06 2007-09 1980-82 1983-85 1986-88 1989-91 1992-94 1995-97 1998-00 2001-03 2004-06 2007-09 0% Niger Cape Verde Gambia Protein Fat Source: Author’s computation using FAO’s Food Balance Sheet data. 75 Guinea Bissau Carbohydrates 1980-82 1983-85 1986-88 1989-91 1992-94 1995-97 1998-00 2001-03 2004-06 2007-09 1980-82 1983-85 1986-88 1989-91 1992-94 1995-97 1998-00 2001-03 2004-06 2007-09 1980-82 1983-85 1986-88 1989-91 1992-94 1995-97 1998-00 2001-03 2004-06 2007-09 1980-82 1983-85 1986-88 1989-91 1992-94 1995-97 1998-00 2001-03 2004-06 2007-09 Figure 2-20. Daily Caloric Share (%) by Macronutrients - Coastal Sahel 100% 90% 80% 70% 60% 50% 40% 30% 20% 10% 0% Senegal Benin Protein Fat Cote d'Ivoire Ghana Carbohydrates 76 1980-82 1983-85 1986-88 1989-91 1992-94 1995-97 1998-00 2001-03 2004-06 2007-09 1980-82 1983-85 1986-88 1989-91 1992-94 1995-97 1998-00 2001-03 2004-06 2007-09 1980-82 1983-85 1986-88 1989-91 1992-94 1995-97 1998-00 2001-03 2004-06 2007-09 1980-82 1983-85 1986-88 1989-91 1992-94 1995-97 1998-00 2001-03 2004-06 2007-09 Figure 2-21. Daily Caloric Share (%) by Macronutrients - Coastal Non-Sahel 100% 90% 80% 70% 60% 50% 40% 30% 20% 10% 0% Guinea Liberia Nigeria Protein Fat Source: Author’s computation using FAO’s Food Balance Sheet data. 77 Sierra leone Carbohydrates 1980-82 1983-85 1986-88 1989-91 1992-94 1995-97 1998-00 2001-03 2004-06 2007-09 1980-82 1983-85 1986-88 1989-91 1992-94 1995-97 1998-00 2001-03 2004-06 2007-09 1980-82 1983-85 1986-88 1989-91 1992-94 1995-97 1998-00 2001-03 2004-06 2007-09 1980-82 1983-85 1986-88 1989-91 1992-94 1995-97 1998-00 2001-03 2004-06 2007-09 Figure 2-21. (cont’d) 100% 90% 80% 70% 60% 50% 40% 30% 20% 10% 0% Togo 2.6. Chapter Summary The goal of this chapter was to provide evidence of shifts in per capita food availability patterns in ECOWAS West Africa. In particular, the analysis was intended to identify major contributors to diets, changes in the levels as well as in the composition of per capita food supply at the country-level and to enhance understanding of the food supply situation within the ECOWAS using national-level FAOSTAT’s food balance sheet data from 1980-2009. The analysis reveals a trend towards greater calorie supply for most ECOWAS countries. The growth in daily energy availability has been much more pronounced and consistent for countries experiencing rapid economic growth (e.g., Ghana and Cape Verde), but has been disrupted in countries that have been through civil disruptions like Cote d’Ivoire, Liberia and Sierra Leone. The analysis also provides evidence of a diversification in the composition of food supply. The relative importance of starchy roots and tubers in total food availability, particularly in the Sahel region, has grown over time. The analysis reveals evidence consistent with the “cassava revolution” that has taken place in some of the Coastal Non-Sahelian countries such as Nigeria, Ghana, and Sierra Leone (Nweke et al., 2002). The growth in the per capita availability of cassava (e.g., Senegal) and sweet potatoes (e.g., Mali) most likely reflects the lower income population shifting towards cheaper calorie sources. Per capita availability of yams also showed huge increases in some Coastal Non-Sahelian countries (e.g., Ghana and Nigeria). There has also been positive growth in the supply of Irish potatoes in some countries (e.g., Cape Verde and Senegal), supporting evidence of a westernization of diets (increased consumption of potato chips/French fries). The analysis also provides evidence of a striking growth in per capita availability of maize in the Sahel (Burkina Faso, Mali, and Senegal). Per capita rice availability increased for most countries in the study period. In Cape Verde, for example, there is been a 78 replacement of maize with rice as the dominant type of cereal. Although food availability is only one dimension of food security, rising starchy staple availability is likely to have a positive impact for food security in the region. With respect to the quality of the per capita food supply, the supply of daily protein per capita has been increasing for most countries since the early 2000s. Proteins from plant sources are the dominant source of protein in the entire region. Although plant protein dominates as the major source of protein for most of these countries, some of these countries (e.g., Niger, Sierra Leone, Nigeria and Cape Verde) derive an important share of vegetable protein from pulses, which are also a source of high-quality protein. Some countries have shown a positive trend in the supply of animal protein. The countries that have shown evidence of diet upgrading through increased per capita availability of animal protein have been mostly those that have also shown evidence of rapid and strong economic growth over time (e.g., Ghana and Cape Verde). Countries with modest economic growth, such as Mali, have also shown modest growth in the consumption of animal protein over time. Apparent per capita daily fat supply increased for most countries in the study period. The share of carbohydrates, fats, and proteins in total daily energy (calorie) supply, however, did not change much over time. While most countries meet and even exceed the WHO/FAO recommended daily allowance (measured as shares) for carbohydrates, the share of protein in daily energy continues to remain close to the lower bound of the recommended daily value. However, this has not always meant that the diets have not improved over time, as some countries have experienced not only a positive growth in the supply of proteins in absolute terms, but also have been improving in terms of the availability of animal protein as well as pulses. Although fish and seafood remain the main animal protein source for 79 most of the coastal states in the ECOWAS zone, most of the countries in the region have experienced growth in the per capita supply of poultry meat over time, primarily from imports. 80 APPENDIX 81 Table A2-1. Food Availability by Major Food Group–Non-Coastal Sahel- Burkina Faso (kg/capita/year) Food Group Cereals - Excl. Beer Starchy R & T 1980 to 1982 148 17 1983 to 1985 148 17 1986 to 1988 196 15 1989 to 1991 217 7 1992 to 1994 229 7 Sugar & Sweeteners 4 4 4 4 4 Pulses 10 9 12 12 13 Oilcrops 6 8 11 9 12 Vegetable Oils 3 4 4 4 4 Fruits Excl. wine 8 8 7 7 7 Vegetables21 23 22 24 23 Meat & offal 9 11 12 15 16 Eggs 1 1 1 2 3 Milk - Excl. Butter 26 22 23 16 16 Fish & Seafood 2 2 2 2 2 Alcoholic Beverages 50 46 55 54 63 Source: Author’s computation using FAO’s Food Balance Sheet data. 82 1995 to 1997 224 6 1998 to 2000 218 6 2001 to 2003 224 6 2004 to 2006 232 7 2007 to 2009 228 8 % change 1980-85 to 2004-09 55% -56% 5 11 11 5 6 21 16 3 17 2 61 4 12 12 5 6 19 17 2 18 2 52 5 12 15 5 6 17 18 2 16 2 55 5 13 12 6 5 17 19 2 17 2 54 5 13 14 6 5 15 18 2 17 2 54 25% 37% 86% 71% -38% -27% 85% 100% -29% 15% 13% Table A2-2. Food Availability by Major Food Group - Mali (kg/capita/year) Food Group 1980 1983 1986 1989 1992 to to to to to 1982 1985 1988 1991 1994 Cereals 125 155 185 181 176 Starchy R&T 4 3 3 5 8 Sugar & Sweeteners 4 4 6 10 10 Pulses 4 4 5 6 10 Vegetable Oils 6 5 7 8 8 Fruits - Excl. Wine 17 17 18 17 19 Vegetables 46 49 51 54 51 Meat & offal 20 19 20 21 18 Eggs 1 1 1 1 1 Milk Excl. Butter 59 47 46 51 51 Fish, Seafood 10 7 7 8 7 Alcoholic Beverages 5 6 7 7 5 Source: Author’s computation using FAO’s Food Balance Sheet data. 83 1995 to 1997 181 9 11 9 7 23 53 18 1 48 11 6 1998 to 2000 181 13 13 12 8 24 52 19 1 52 9 5 2001 to 2003 189 18 13 11 8 26 52 21 1 52 9 6 2004 to 2006 198 26 13 10 8 30 47 23 0 57 9 6 2007 to 2009 204 32 12 7 8 28 52 25 0 63 8 6 % change 1980-85 to 2004-09 44% 729% 213% 113% 45% 71% 4% 23% -100% 13% 0% 9% Table A2-3. Food Availability by Major Food Group–Non-Coastal Sahel - Niger (kg/capita/year) Food Group 1980 1983 1986 1989 1992 to to to to to 1982 1985 1988 1991 1994 Cereals Excl. Beer 197 201 199 211 200 Starchy R & T 31 32 29 21 14 Sugar & Sweeteners 4 7 7 5 3 Pulses 23 18 18 15 14 Vegetable Oils 3 3 2 3 2 Fruits - Excl. Wine 7 7 6 6 5 Vegetables 21 16 16 30 34 Meat and offal 27 22 19 20 21 Eggs 1 1 1 1 1 Fish & Seafood 1 0 0 1 0 Milk Excl. Butter 57 52 42 40 40 Alcoholic Beverages 2 1 1 1 0 Source: Author’s computation using FAO’s Food Balance Sheet data. 84 1995 to 1997 200 17 6 14 4 5 41 21 1 1 43 1 1998 to 2000 200 22 7 24 4 6 49 23 0 1 45 1 2001 to 2003 202 14 6 19 5 10 54 25 0 1 48 0 2004 to 2006 200 14 7 23 5 12 49 27 0 3 49 0 2007 to 2009 209 13 6 36 4 15 51 28 0 3 59 1 %change 1980-85 to 2004-09 3% -57% 18% 44% 50% 93% 170% 12% -100% 218% -1% -67% Table A2-4. Food Availability by Major Food Group - Coastal Non-Sahel- Benin (kg/capita) Food Group 1980 1983 1986 1989 1992 to to to to to 1982 1985 1988 1991 1994 Cereals – Excl. Beer 93 92 97 109 107 Starchy R&T 205 212 229 268 266 Sugar & Sweeteners 0 2 3 4 6 pulses 6 7 8 9 9 Oilcrops 7 7 7 8 8 Vegetable Oils 9 9 6 6 5 Fruits Excl. wine 36 35 33 34 31 Vegetables37 38 42 43 46 Meat & offal 13 16 13 11 13 Eggs 2 2 2 1 1 Milk – Excl. Butter 8 8 8 6 6 Fish & Seafood 12 10 11 9 10 Alcoholic Beverages 14 12 12 12 11 Source: Author’s computation using FAO’s Food Balance Sheet data. 85 1995 to 1997 108 283 7 9 9 5 32 49 12 1 8 10 12 1998 to 2000 108 287 6 10 9 7 29 54 14 1 12 8 11 2001 to 2003 108 289 6 10 10 8 30 49 17 1 11 9 12 2004 to 2006 114 278 4 12 9 9 30 48 14 1 10 9 14 2007 to 2009 115 296 6 17 8 7 37 48 20 1 8 8 15 % change 1980-85 to 2004-09 24% 38% 400% 123% 21% -11% -6% 28% 17% -50% 13% -23% 12% Table A2-5. Food Availability by Major Food Group–Coastal Non-Sahel - Cote d'Ivoire (kg/capita) Food Group 1980 1983 1986 1989 1992 to to to to to 1982 1985 1988 1991 1994 Cereals – Excl. Beer 116 111 105 99 98 Starchy R&T 314 295 282 274 268 Sugar & Sweeteners 10 10 11 10 10 Oilcrops 5 4 4 4 4 Vegetable Oils 10 10 9 10 10 Fruits Excl. wine 106 92 87 83 88 Vegetables40 39 37 43 41 Meat & offal 22 21 20 20 17 Eggs 1 1 1 1 1 Milk – Excl. Butter 21 18 21 14 13 Fish & Seafood 18 16 20 18 14 Alcoholic Beverages 44 40 36 33 31 Source: Author’s computation using FAO’s Food Balance Sheet data. 86 1995 to 1997 96 269 9 4 11 91 39 14 1 9 13 35 1998 to 2000 89 286 8 5 12 90 34 13 2 7 14 34 2001 to 2003 90 281 9 5 13 74 39 14 2 7 14 40 2004 to 2006 92 287 10 4 12 75 37 16 1 8 14 44 2007 to 2009 102 309 9 4 11 76 35 16 1 7 13 46 % change 1980-85 to 2004-09 -15% -2% -5% -11% 15% -24% -9% -26% 0% -62% -21% 7% Table A2-6. Food Availability by Major Food Group–Coastal Non-Sahel-Ghana (kg/capita) Food Group Cereals – Excl. Beer 1980 to 1982 56 1983 to 1985 63 1986 to 1988 67 1989 to 1991 75 1992 to 1994 92 1995 to 1997 83 1998 to 2000 83 2001 to 2003 91 2004 to 2006 97 2007 to 2009 90 % change 1980-85 to 2004-09 57% Starchy R&T 216 239 273 283 331 396 402 404 381 403 72% Sugar & Sweeteners 2 2 6 6 7 5 6 7 10 11 425% Oilcrops 22 17 13 11 11 12 13 13 13 13 -33% Vegetable Oils 5 6 7 7 7 5 6 6 8 9 55% Fruits Excl. wine 79 92 83 69 82 106 111 117 136 158 72% Vegetables 20 18 23 25 24 31 34 31 34 34 79% Meat & offal 11 12 11 11 11 10 10 11 13 15 22% Eggs Milk – Excl. Butter 1 2 0 5 0 4 1 4 1 3 1 2 1 5 1 7 1 8 1 8 100% 129% Fish & Seafood 21 21 26 25 24 28 31 25 28 29 36% Alcoholic Beverages 18 17 18 18 24 25 22 20 21 23 26% Source: Author’s computation using FAO’s Food Balance Sheet data. 87 Table A2-7. Food Availability by Major Food Group–Coastal Non-Sahel – Guinea (kg/capita) Food Group 1983 to 1985 123 1986 to 1988 135 1989 to 1991 131 1992 to 1994 129 1995 to 1997 127 1998 to 2000 125 2001 to 2003 126 2004 to 2006 126 2007 to 2009 136 % change 198085 to 2004-09 Cereals – Excl. Beer 1980 to 1982 118 Starchy R&T 119 112 111 115 114 113 117 116 123 126 8% Sugar & Sweeteners 5 8 10 9 10 11 12 11 12 13 92% Pulses 7 7 8 8 8 7 7 6 6 6 -14% Oilcrops 4 4 3 3 4 4 4 5 6 6 50% Vegetable Oils 12 11 10 10 13 13 13 13 15 15 30% Fruits Excl. wine 117 116 114 117 119 110 104 106 103 104 -11% Vegetables 82 77 73 68 65 60 57 55 55 51 -33% Meat & offal 5 5 4 5 6 7 7 8 9 10 90% Eggs Milk – Excl. Butter 1 10 1 12 1 11 1 10 1 12 1 12 1 13 2 12 2 13 2 14 100% 23% Fish & Seafood 7 8 8 9 11 11 12 13 11 10 40% Alcoholic Beverages 1 1 1 2 2 1 2 2 2 2 100% Source: Author’s computation using FAO’s Food Balance Sheet data. 88 9% Table A2-8. Food Availability by Major Food Group-Coastal Non-Sahel- Liberia (kg/capita) Food Group Cereals - Excl. Beer 1980 to 1982 132 1983 to 1985 126 1986 to 1988 123 1989 to 1991 112 1992 to 1994 91 1995 to 1997 98 1998 to 2000 97 2001 to 2003 86 2004 to 2006 93 2007 to 2009 107 % change 1980-85 to 2004-09 -22% Starchy R&T 173 140 190 179 156 132 160 178 166 161 4% Sugar & Sweeteners 5 7 7 5 5 5 5 5 6 7 8% Oilcrops 5 5 5 5 6 5 4 4 4 3 -30% Vegetable Oils 12 15 12 12 18 19 17 16 17 16 22% Fruits Excl. wine 57 55 48 48 56 62 53 51 48 46 -16% Vegetables 31 33 34 32 35 34 27 23 23 24 -27% Meat & offal 13 12 13 10 12 11 10 9 10 11 -16% Eggs Milk - Excl. Butter 1 10 2 13 2 8 2 4 2 3 2 3 2 3 1 2 2 4 2 3 33% -70% Fish & Seafood 13 15 15 10 6 6 6 4 5 5 -64% Alcoholic Beverages 11 11 11 9 10 10 8 7 8 8 -27% Source: Author’s computation using FAO’s Food Balance Sheet data. 89 Table A2-9. Food Availability by Major Food Group-Coastal Non-Sahel -Nigeria (kg/capita) Food Group Cereals - Excl. Beer 1980 to 1982 97 1983 to 1985 103 1986 to 1988 123 1989 to 1991 124 1992 to 1994 133 1995 to 1997 137 1998 to 2000 137 2001 to 2003 133 2004 to 2006 141 2007 to 2009 145 % change 1980-85 to 2004-09 43% Starchy R&T 107 95 111 166 231 235 238 210 215 223 117% Sugar & Sweeteners 11 8 6 5 6 7 8 10 10 10 5% Pulses 4 4 5 8 8 9 10 9 9 10 138% Oil Crops 5 4 4 5 5 6 7 7 8 8 78% Vegetable Oils 11 9 10 12 14 13 13 14 15 15 50% Fruits Excl. wine 61 62 58 61 66 64 65 63 62 59 -2% Vegetables 38 39 41 44 47 52 57 57 60 59 55% Meat & offal 11 11 9 8 8 9 9 10 9 10 -12% Eggs Milk - Excl. Butter 3 15 3 9 3 5 3 6 4 6 3 6 3 5 3 7 3 8 4 8 34% -34% Fish & Seafood 16 9 7 10 6 7 7 9 9 13 -10% Alcoholic Beverages 75 67 65 60 59 62 69 68 69 67 -4% Source: Author’s computation using FAO’s Food Balance Sheet data. 90 Table A2-10. Food Availability by Major Food Group–Coastal Non-Sahel- Sierra Leone (kg/capita) Food Group Cereals - Excl. Beer Starchy R&T Sugar & Sweeteners Pulses Oilcrops Vegetable Oils Fruits Excl. wine Vegetables Meat & offal Eggs Milk - Excl. Butter 1980 to 1982 1983 to 1985 1986 to 1988 1989 to 1991 1992 to 1994 1995 to 1997 1998 to 2000 2001 to 2003 2004 to 2006 2007 to 2009 % change 1980-85 to 2004-09 117 37 7 8 3 18 36 46 6 1 16 111 36 6 8 3 16 37 47 5 1 9 113 34 5 8 5 17 37 45 5 1 9 115 34 5 8 4 16 36 43 6 1 8 112 45 5 8 5 16 36 44 6 1 8 107 79 4 9 7 16 36 44 6 2 5 114 69 5 11 5 13 36 42 6 2 3 112 71 5 12 6 12 36 46 7 2 4 110 68 6 13 9 13 35 47 7 1 5 116 74 7 12 7 14 36 47 8 2 5 -1% 95% 0% 56% 167% -21% -3% 1% 36% 50% -60% 14 44 15 44 18 50 27 49 25 51 33% 6% Fish & Seafood 22 17 14 14 14 Alcoholic Beverages 46 48 46 44 43 Source: Author’s computation using FAO’s Food Balance Sheet data. 91 Table A2-11. Food Availability by Major Food Group–Coastal Non-Sahel – Togo (kg/capita) Food Group 1980 1983 1986 1989 1992 1995 to to to to to to 1982 1985 1988 1991 1994 1997 Cereals - Excl. Beer 98 102 100 111 112 116 Starchy R&T 243 200 177 187 178 188 Sugar & Sweeteners 8 9 7 5 2 3 Pulses 8 8 7 5 7 9 oilcrops 6 5 4 5 6 5 Vegetable Oils 4 4 5 7 6 8 Fruits Excl. wine 13 12 12 11 10 9 Vegetables 23 25 30 39 37 31 Meat & offal 8 9 11 9 8 7 Eggs 0 1 1 1 1 1 Milk - Excl. Butter 4 4 4 5 4 5 Fish & Seafood 11 10 12 12 11 14 Alcoholic Beverages 28 24 25 18 14 13 Source: Author’s computation using FAO’s Food Balance Sheet data. 92 1998 to 2000 115 202 4 8 5 7 9 25 8 1 3 10 10 2001 to 2003 119 187 4 8 7 8 8 25 9 1 4 7 10 2004 to 2006 123 185 6 8 7 9 8 26 9 1 6 7 11 2007 to 2009 130 198 8 10 7 9 9 29 11 1 5 7 14 % change 1980-85 to 2004-09 27% -14% -19% 15% 24% 126% -32% 14% 20% 85% 37% -29% -52% Table A2-12. Food Availability by Major Food Group - Coastal Sahel-Cape Verde (kg/capita) Food Group 1980 1983 1986 1989 1992 to to to to to 1982 1985 1988 1991 1994 Cereals –Excl. Beer 152 160 152 137 140 Starchy R& T 33 22 57 51 33 Sugar & Sweeteners 13 16 16 17 19 Pulses 12 14 27 16 6 Oilcrops 17 15 11 9 7 Vegetable Oils 6 8 10 8 13 Fruits Excl. wine 32 30 31 33 44 Vegetables 5 8 20 24 26 Meat & offal 9 10 14 16 26 Eggs 1 1 1 1 4 Milk –Excl. Butter 65 72 65 59 80 Fish & Seafood 34 29 15 17 14 Alcoholic Beverages 12 14 17 17 24 Source: Author’s computation using FAO’s Food Balance Sheet data. 93 1995 to 1997 124 33 20 8 7 13 49 33 22 5 83 18 24 1998 to 2000 128 38 22 9 7 8 44 43 26 5 82 20 30 2001 to 2003 123 42 26 8 8 8 44 46 30 4 87 19 33 2004 to 2006 125 45 25 8 7 9 53 53 37 4 107 14 38 2007 to 2009 126 48 23 11 7 8 75 61 45 4 124 12 40 % change 1980-85 to 2004-09 -20% 69% 66% -27% -56% 21% 106% 777% 332% 300% 69% -59% 200% Table A2-13. Food Availability by Major Food Group–Coastal Sahel- Gambia (kg/capita) Food Group 1980 1983 1986 1989 1992 to to to to to 1982 1985 1988 1991 1994 Cereals - Excl. Beer 145 153 170 160 145 Starchy R& T 9 9 8 8 8 Sugar & Sweeteners 20 30 48 48 37 Oilcrops 5 7 7 7 7 Vegetable Oils 10 10 10 12 16 Fruits Excl. wine 5 5 4 4 3 Vegetables 12 11 20 29 35 Meat & offal 11 10 10 10 8 Eggs 1 1 1 1 1 Milk - Excl. Butter 25 34 28 16 18 Fish & Seafood 16 17 16 22 18 Alcoholic Beverages 16 20 28 23 22 Source: Author’s computation using FAO’s Food Balance Sheet data. 94 1995 to 1997 140 6 36 7 14 4 27 7 1 17 24 21 1998 to 2000 137 9 32 8 17 5 31 7 1 24 23 31 2001 to 2003 141 10 26 7 18 5 27 6 1 28 29 33 2004 to 2006 140 11 28 6 18 4 34 10 2 24 24 35 2007 to 2009 175 9 28 6 15 6 32 9 2 30 28 35 % change 1980-85 to 2004-09 6% 11% 12% 0% 65% 0% 187% -10% 100% -8% 58% 94% Table A2-14. Food Availability by Major Food Group–Coastal Sahel – Guinea Bissau (kg/capita) Food Group Cereals - Excl. Beer 1980 to 1982 139 1983 to 1985 146 1986 to 1988 140 1989 to 1991 143 1992 to 1994 148 1995 to 1997 140 1998 to 2000 138 2001 to 2003 145 2004 to 2006 146 2007 to 2009 145 % change 1980-85 to 2004-09 2% Starchy R& T Sugar & Sweeteners 46 3 50 3 68 2 63 3 59 2 64 4 71 4 69 6 69 12 75 7 50% 217% Oilcrops 4 3 4 4 4 4 4 3 4 11 114% Vegetable Oils 9 11 12 11 13 11 11 12 12 16 40% Fruits Excl. wine 43 44 48 51 52 50 48 46 44 15 -32% Vegetables 20 18 17 17 17 18 17 16 16 40 47% Meat & offal 15 15 15 15 16 16 16 16 15 17 7% Eggs 0 0 0 0 0 1 1 1 1 1 - Milk - Excl. Butter 16 17 21 20 21 17 15 15 15 16 -6% Fish & Seafood 3 2 4 4 5 5 4 2 2 1 -40% Alcoholic Beverages 31 31 26 24 25 23 20 21 29 26 -11% Source: Author’s computation using FAO’s Food Balance Sheet data. 95 Table A2-15. Food Availability by Major Food Group–Coastal Sahel-Senegal (kg/capita) Food Group 1980 to 1982 177 1983 to 1985 180 1986 to 1988 175 1989 to 1991 179 1992 to 1994 157 1995 to 1997 154 1998 to 2000 150 2001 to 2003 154 2004 to 2006 163 2007 to 2009 167 % change 1980-85 to 2004-09 -8% Starchy R& T 8 7 11 9 9 7 13 18 23 29 247% Sugar & Sweeteners 16 14 11 15 15 18 14 14 13 15 -7% Oilcrops Vegetable Oils 11 11 7 12 9 7 7 9 6 15 5 15 4 15 5 15 6 14 5 16 -39% 30% Fruits Excl. wine 12 12 13 13 13 14 13 15 14 17 29% Vegetables 17 16 20 27 27 43 47 53 56 64 264% Meat & offal Eggs Milk - Excl. Butter 13 1 36 13 1 44 15 1 43 14 1 39 14 1 42 13 1 29 13 1 27 14 2 23 15 2 29 17 2 32 23% 100% -24% Fish & Seafood 23 21 24 26 34 Alcoholic Beverages 5 4 4 4 4 Source: Author’s computation using FAO’s Food Balance Sheet data. 31 4 30 4 28 4 27 4 24 3 16% -22% Cereals - Excl. Beer 96 Table A2-16. Starchy Staples Availability (kg/capita/year) - Non-Coastal Sahel 1980 1983 1986 1989 1992 1995 1998 2001 2004 2007 Absolute to to to to to to to to to to change 1982 1985 1988 1991 1994 1997 2000 2003 2006 2009 1980-85 to 200409 Burkina Faso Wheat 4 4 4 3 5 7 7 3 7 7 3 Rice (Milled) 7 14 13 13 15 21 21 20 19 18 8 Maize 16 15 20 34 28 30 35 39 45 49 32 Millet 49 49 69 78 76 65 70 70 72 65 20 Sorghum 71 66 89 87 104 99 82 89 88 87 19 Cassava 4 3 1 0 0 0 0 0 0 0 -4 Sweet Potatoes 4 3 3 2 1 1 2 3 4 4 1 Yams 10 10 11 4 5 4 4 3 3 3 -7 Mali Wheat 6 7 9 5 4 4 8 8 9 9 3 Rice (Milled) 22 25 27 26 32 39 50 50 54 55 31 Maize 8 16 20 18 20 23 23 26 28 29 17 Millet 47 58 75 70 56 61 54 59 62 64 11 Sorghum 37 45 52 60 62 53 44 44 44 44 3 Potatoes 0 0 0 2 5 5 5 6 7 4 6 Sweet potatoes 1 1 1 1 1 1 3 6 10 19 14 Cassava 0 0 0 0 0 0 1 2 3 1 2 Yams 2 2 1 1 1 1 3 3 4 6 3 Niger Wheat 6 7 6 8 7 4 5 6 5 5 -2 Rice (Milled) 8 11 10 10 9 10 12 18 20 11 6 Maize 2 3 2 1 1 3 6 4 4 2 1 Millet 136 142 140 155 149 147 145 141 130 148 0 Sorghum 44 38 40 37 35 35 30 33 39 42 -1 Cassava 28 25 24 16 9 13 16 10 9 8 -18 Sweet Potatoes 3 7 5 4 4 4 4 3 3 3 -2 Source: Author’s computation using FAO’s Food Balance Sheet data. 97 Table A2-17. Starchy Staples Availability (kg/capita) in Selected Countries in Coastal Sahel 1980 1983 1986 1989 1992 1995 1998 2001 2004 2007 Absolute to to to to to to to to to to change 1982 1985 1988 1991 1994 1997 2000 2003 2006 2009 1980-85 to 200409 Cape Verde Wheat 41 45 45 35 37 35 36 37 38 43 -3 Rice (Milled) 17 21 22 24 29 34 39 41 50 49 31 Maize 94 94 85 78 75 52 53 44 36 32 -60 Cassava 8 5 14 12 7 7 7 6 7 8 1 Potatoes 10 12 14 13 17 17 22 26 29 29 18 Sweet potatoes 14 6 29 27 7 7 8 8 8 10 -1 Senegal Wheat 20 19 19 25 23 23 25 28 30 33 12 Rice (Milled) 68 66 60 64 57 62 69 69 69 74 5 Maize 13 16 17 16 14 11 9 11 27 28 13 Millet 54 54 62 60 51 47 36 34 28 25 -28 Sorghum 21 24 16 15 12 11 11 12 9 8 -14 Cassava 4 3 8 6 6 4 9 12 16 19 14 Potatoes 2 3 3 3 3 2 3 3 5 6 3 Sweet Potatoes 1 1 1 0 0 0 1 3 2 3 2 Source: Author’s computation using FAO’s Food Balance Sheet data. 98 Table A2-18. Starchy Staples Availability (kg/capita/year) in Selected Coastal Non-Sahel Countries 1980 to 1982 1983 to 1985 1986 to 1988 1989 to 1991 1992 to 1994 1995 to 1997 Benin Wheat 14 9 11 11 12 9 Rice (Milled) 7 11 10 16 17 20 Maize 56 53 56 60 58 60 Millet 1 1 3 3 3 3 Sorghum 15 17 17 17 16 15 Cassava 116 118 119 145 145 160 Sweet Potatoes 8 8 7 6 7 9 Yams 81 86 102 116 114 114 Cote d'Ivoire Wheat 22 20 20 17 15 14 Rice (Milled) 61 59 56 54 53 53 Maize 29 28 26 24 26 26 Millet 1 1 2 2 2 2 Sorghum 2 1 1 1 1 1 Cassava 109 106 102 100 98 101 Potatoes 1 1 1 1 1 1 Sweet Potatoes 1 1 2 2 2 2 Yams 189 177 170 166 165 162 Source: Author’s computation using FAO’s Food Balance Sheet data. 99 1998 to 2000 2001 to 2003 2004 to 2006 2007 to 2009 Absolute change 1980-85 to 2004-09 9 12 67 3 17 144 8 134 8 18 61 3 18 144 8 137 5 31 58 3 16 137 6 135 9 33 57 3 13 146 7 143 -5 23 3 2 -2 25 -2 56 16 46 23 2 1 110 1 3 170 16 50 21 1 1 103 1 2 172 15 53 20 1 1 101 1 2 180 16 64 19 1 1 110 1 2 193 -6 -2 -9 0 -1 -2 0 1 4 Table A2-18 con'td. Starchy Staples Availability (kg/capita/year) in Selected Coastal Non-Sahel Countries 1980 to 1982 1983 to 1985 1986 to 1988 1989 to 1991 1992 to 1994 Ghana Wheat 10 8 10 12 12 Rice (Milled) 6 7 9 12 17 Maize 25 33 34 36 43 Millet 7 7 7 6 7 Sorghum 8 8 8 9 12 Cassava 126 120 148 163 198 Sweet Potatoes 0 0 0 0 0 Yams 45 68 64 61 74 Other roots 45 51 60 59 59 Nigeria Wheat 16 14 6 4 9 Rice (Milled) 16 14 15 21 20 Maize 7 9 28 31 33 Millet 24 28 32 35 32 Sorghum 33 37 42 34 39 Cassava 81 74 84 115 155 Sweet Potatoes 1 1 1 1 2 Yams 24 20 25 48 72 Potatoes 0 0 0 0 1 Source: Author’s computation using FAO’s Food Balance Sheet data. 100 1995 to 1997 1998 to 2000 2001 to 2003 2004 to 2006 2007 to 2009 Absolute change 1980-85 to 2004-09 8 11 43 8 13 231 3 95 67 13 12 40 6 11 219 5 110 69 11 22 42 6 9 215 4 117 67 16 24 41 6 9 206 4 114 57 18 27 28 6 10 212 5 132 55 8 19 6 -1 2 86 5 67 8 8 20 29 36 44 151 9 72 0 15 22 22 36 43 144 12 74 2 17 23 20 32 40 114 14 73 3 18 22 23 35 43 116 16 72 3 4 3 7 15 9 8 39 15 50 4 Table A2-19. Daily Protein Availability by Source (kg/capita) Non-Coastal Sahel 1980 to 1982 1983 to 1985 1986 to 1988 1989 to 1991 1992 to 1994 1995 to 1997 1998 to 2000 Burkina Faso Plant 47 47 61 64 70 67 66 Animal 7 7 8 8 9 10 10 Total 54 54 69 72 79 77 76 Mali Plant 31 37 44 45 47 47 49 Animal 17 15 15 17 15 16 16 Total 48 52 59 62 62 63 65 Niger Plant 48 45 45 44 42 42 49 Animal 17 14 12 12 12 13 14 Total 65 59 57 56 54 55 63 Source: Author’s computation using FAO’s Food Balance Sheet data. 101 2001 to 2003 2004 to 2006 2007 to 2009 % change 1980-85 to 2004-09 % of total change 69 10 79 70 10 80 71 10 81 50.0% 42.9% 49.1% 88.7% 11.3% 51 16 67 52 18 70 53 19 72 54.4% 15.6% 42.0% 88.1% 11.9% 48 15 63 52 16 68 62 18 80 22.6% 9.7% 19.4% 87.5% 12.5% Table A2-20. Daily Protein Availability by Source (g/capita) Coastal Sahel 1980 to 1982 1983 to 1985 1986 to 1988 1989 to 1991 1992 to 1994 1995 to 1997 1998 to 2000 Cape Verde Plant 45 48 55 45 39 37 Animal 20 19 16 17 22 22 Total 65 67 71 62 61 59 Gambia Plant 37 39 43 41 39 37 Animal 11 12 12 13 11 12 Total 48 51 55 54 50 49 Guinea Bissau Plant 36 37 36 36 36 35 Animal 8 8 9 9 9 9 Total 44 45 45 45 45 44 Senegal Plant 50 49 49 48 42 41 Animal 15 16 18 18 20 17 Total 65 65 67 66 62 58 Source: Author's calculations using FAO’sFood Balance Sheet data. Note: * Represents the percentage of the decline in total protein supply. 102 2001 to 2003 2004 to 2006 2007 to 2009 % change 1980-85 to 2004-09 % of total change 39 24 63 37 25 62 39 28 67 41 32 73 -14.0% 53.8% 6.1% -162.5% 262.5% 38 13 51 40 14 54 40 14 54 45 15 60 11.8% 26.1% 15.2% 60.0% 40.0% 34 8 42 35 8 43 36 7 43 37 8 45 0.0% -6.3% -1.1% 0.0% 100.0% 42 17 59 37 16 53 41 17 58 44 17 61 -14.1% 9.7% -8.5% *127.3% *-27.3% Table A2-21. Daily Protein Availability by Source (g/capita) in Selected Countries in Coastal Non-Sahel 1980 to 1982 1983 to 1985 1986 to 1988 1989 to 1991 1992 to 1994 1995 to 1997 Benin Plant 36 37 40 45 45 46 Animal 10 10 9 8 9 8 Total 46 47 49 53 54 54 Ghana Plant 26 28 31 31 37 38 Animal 12 13 14 14 14 14 Total 38 41 45 45 51 52 Nigeria Plant 32 33 39 43 46 49 Animal 11 8 7 7 6 7 Total 43 41 46 50 52 56 Source: Author's calculations using FAO’s Food Balance Sheet data. 103 1998 to 2000 2001 to 2003 2004 to 2006 2007 to 2009 % change 1980-85 to 2004-09 % of total change 47 9 56 48 10 58 49 9 58 52 10 62 38.4% -5.0% 29.0% 103.7% -3.7% 39 15 54 41 14 55 42 16 58 43 17 60 57.4% 32.0% 49.4% 79.5% 20.5% 51 7 58 50 8 58 53 8 61 55 9 64 66.2% -10.5% 48.8% 104.9% -4.9% CHAPTER 3. AGGREGATE-LEVEL DETERMINANTS OF STARCHY STAPLES DEMAND IN WEST AFRICA: THE CASE OF BENIN, MALI AND SENEGAL 3.1. Background and Problem Statement Studies on food demand in West Africa (WA) are generally very few, and most were conducted between the late 1980s and late 1990s (Reardon et al. 198822; Delgado, 198923; Rogers and Lowdermilk, 199124 and Diagana et al. 1999). Still, a few consumption studies have been conducted in the 2000s (Camara, 2004; Joseph and Wodon, 2008; and Taoundyande and Yade, 2012). Knowledge of food demand parameters and of how consumption patterns have changed over time is critical for informed policymaking. Sadoulet and de Janvry (1995) also observe that food demand estimates are essential for planned investments and future prosperity of business ventures in a country. However, in WA information on food demand parameters is limited, thus restricting policymakers’ ability to make sound food policy decisions. An attempt is made in this chapter to bridge this gap by estimating a Linear Approximate Almost Ideal Demand System (LA-AIDS) for starchy staples in Benin, Mali, and Senegal. National aggregate-level demand is the sum of demand by all groups within a country at a given point in time. Rapid population growth, high urbanization rates, growth in per capita incomes, and changes in relative prices have been identified as factors influencing aggregate-level shifts in food consumption in WA (Delgado and Reardon, 1991; Staatz et al. 2008; Taoundyande and Yade, 2012; and Kelly et al. 2012). The size of the population has an obvious effect on aggregate food demand—more people mean more food demand because everyone needs food to survive. The 22 Using data household-level data from urban Burkina Faso Using country level data for Burkina Faso, Cote d’Ivoire, Mali, Niger and Senegal 24 Using household-level data from urban Mali. 104 23 location of the population (urban/rural) also affects food availability and consumption patterns. A shift to urban living entails important changes in lifestyles, economic activities, expanded food choices, and different food consumption observations and experiences. These changes can encourage structural shifts away from traditional diets towards quite different food consumption patterns (Desisle, 1990). In WA, the degree of urbanization is hypothesized to be a significant determinant of shifts in consumption away from traditional coarse grains towards rice and wheat (Delgado and Miller, 1985; Delgado, 1989; Reardon et al. 1988; Kennedy and Reardon, 1994; Rogers and Lowdermilk, 1991; Delgado and Reardon, 1991). Economic considerations also play an important role in determining food demand. By Engel’s law, the proportion of income spent on food is expected to fall as income rises. Also, the composition of food demanded is expected to vary with income level. The specific effects of urbanization on consumption also differ depending on economic conditions (Regmi and Dyck, 2001). When urbanization is accompanied by rising per capita incomes (e.g., due to better employment opportunities), there is likely to be an increase in per capita consumption, the quality of diets is also likely to improve, and other factors (such as the opportunity cost of time) become important in determining food choices. The role of relative cereal prices in determining cereal expenditure patterns has been an important debate in WA. Using aggregate country-level data from Burkina Faso, Cote d’Ivoire, Mali, Niger, and Senegal, Delgado et al. (1989) examined aggregate food demand. In all countries except Senegal, they did not find cereals prices to be a significant factor. Delgado and Reardon (1991) examined the period from the 1970 to 1986, during which world cereals prices as a group fell about one-third relative to the price of manufactured goods. Rice prices in particular were more than one-third cheaper relative to the world price of sorghum during 1982-1986 compared to the 105 late 1960s. Contrary to Delgado (1989), Delgado and Reardon (1991) found that relatively low rice prices were responsible for the shift towards rice from sorghum, noting that changing relative prices have promoted past substitution in cereals consumption patterns but that the substitution process could be reversed if rice and wheat prices were to increase very substantially over those of millet and sorghum. In the current global food situation, an understanding of how food demand responds to changes in structural factors and food prices is crucial. 3.2. Research Objective and Hypotheses This chapter examines aggregate-level determinants of food demand for Benin, Mali, and Senegal using a theoretically appropriate framework for demand analysis. The choice of the countries is limited by the availability of starchy staples price data in capital city markets in the period 19902009. An individual country analysis is carried out for all three countries. Demand parameters are expected to vary across these countries because of differences in taste and preferences, availability of substitutes, as well as differences in income levels. The approach allows testing for the role that various long-term trends and structural factors have on starchy staples consumption patterns, as well as the role of long-term trends in relative prices and real per capita GDP in influencing aggregate food demand. The following hypotheses will be tested: Hypothesis 3.1: Holding other factors constant (e.g., relative cereal prices), there is a negative relationship between the share of urban population and the demand for traditional coarse grains such as millet and sorghum. When urbanization is accompanied by increased employment outside the home, the opportunity of cost of time involved in the preparation of coarse grains becomes an important consideration in consumption choices—the higher the time involved in preparation, the less preferred the commodity is to urban consumers. 106 Hypothesis 3.2: The cross-price elasticities between traditional coarse grains (millet and sorghum) and rice are positive. Hypothesis 3.3: Demands for traditional coarse grains are income-inelastic. Hypothesis 3.4: For Mali, with a more diversified cereal basket (greater availability of substitutes), the cross-price effects will be greater than in the countries with less diversified cereal baskets (Senegal — predominantly rice; and Benin—predominantly maize). 3.3. Data and Methodology National-level per capita availability data (kg/year) for the period 1990-2009 were obtained for Benin, Mali, and Senegal from FAO’s FBS. Monthly nominal retail prices by major starchy staple type from the capital city markets of Benin, Mali, and Senegal over the period 1990-2009 were obtained from each country’s national agricultural statistics office or market information service. Annual average prices per starchy staple type are calculated from the monthly price series. Data on urban population shares over 1990-2009 per country were obtained from the World Development Indicators.25 Annual expenditure by major starchy staple type is calculated by multiplying the annual per capita supply by the annual average of deflated prices. Total expenditure is computed as the sum of expenditures on all major starchy staples. The expenditure share for a starchy staple type is the ratio of expenditure on the starchy staple type to the total expenditure on all starchy staples. To assess the statistical relationship between prices, urbanization, per capita income, and the consumption of starchy staples, a theoretically consistent demand model is used. The Almost Ideal 25 The indicators are available at http://data.worldbank.org/indicator and were last assessed on 01/25/2013. 107 Demand System (AIDS) of Deaton and Muellbauer (1980) has been a popular functional form to model demand behavior. The AIDS specification allows estimation of multivariate demand equations for interrelated commodities and ensures that the system is consistent with consumer theory (Deaton and Muellbauer 1980). It also has the advantage of being flexible and allowing tests of underlying demand and preference restrictions. As a member of the Price-Independent Generalized Logarithmic class of demand models (Muellbauer, 1976), the AIDS model has budget shares that are linear functions of log total expenditure. Despite the advantages of the AIDS model, there is increasing evidence that higher order terms in total expenditure may be required for at least some of the budget share equations (Lewbel, 1991; Blundell et al., 1993). The AIDS model is linear in log expenditure and it makes the restrictive assumption that expenditure elasticities are constant at all expenditure levels (Bopape, 2006). In this study, no formal test is carried out to investigate the appropriateness of the AIDS or the Quadratic Almost Ideal Demand System (QUAIDS) model. Moreover, the QUAIDS model estimates a larger number of parameters than the AIDS model. With the short data series available for this section, the estimation of several parameters will pose a degrees of freedom problem. 3.4. Aggregate Food Demand Model Specification and Estimation Method A common problem in system demand equations is over-parameterization. This problem is dealt with by assuming separability–choosing only a subset of related commodities to include in the system and including only the total expenditures on these commodities. Separability requires that the utility function be separable so that the consumer engages in multi-stage budgeting. The analysis in this chapter is based on a two-stage budgeting approach under the assumption of weak separability. The idea is that: i) the majority of households are low-income, with food taking up a 108 significant share of total budget expenditures; and ii) starchy staples are a major share of household’s food budget. Therefore, consumption expenditures are first allocated between starchy staples and other consumption goods. Conditional on that choice, the starchy staples budget is allocated to individual starchy staple types. This chapter examines the factors that influence the allocation of the starchy staples budget to individual starchy staple types within a systems framework. For the Sahelian countries–Mali and Senegal–starchy staples are predominantly cereals while for a non-Sahelian country, such as Benin, roots and tubers (yams and cassava) are also important starchy staples. For each country a complete price data series is available from 19902009. With the FAO’s FBS per capita availabilty data ending in 2009, the resultant sample period for each country has 20 annual observations, which are analyzed separately. Furthermore, the starchy staples demand model is specified to account for the possibility of structural change originating from the 1994 devaluation of the CFA franc. Presumably, the devaluation of the CFA franc acted through its impact on incomes and relative prices. However, if it led to changes in consumption habits or changes in income distribution, it could have had a structural effect. To explore this, the model specification includes a dummy variable for the year of the devaluation. The n-good system specification of the AIDS share equations for modeling the determinants of starchy staples demand (budget stage two), augmented to allow for the urban population share to influence the intercept term, is formulated as follows: 𝑤𝑖𝑡 = 𝛼𝑖 + 𝜃𝑖 𝑆𝐻𝐴𝑅𝐸_𝑈𝑅𝐵𝑡 + 𝜏𝑖 𝑑1 + ∑ 𝑛 𝑗=1 𝛾𝑖𝑗 𝑙𝑛𝑝jit + 𝛽𝑖 𝑙𝑛 [ 𝑋𝑡 ] + 𝜀𝑖𝑡 𝑎(𝒑) (3 − 1) The dependent variable ( 𝑤𝑖𝑡 ) is the budget share associated with starchy staple type 𝑖 ̇ at time t. 𝑑1 is a dummy variable which takes the value 1 if year >=1994 and 0 otherwise. 𝛼𝑖 is the 109 constant coefficient in the 𝑖̇th share equation, and 𝛾𝑖𝑗 is the slope coefficient associated with the jth starchy staple type in the 𝑖̇th share equation. 𝑝jit is the normalized real price of starchy staple type j in the share equation for starchy staple type 𝑖̇ at time t. 𝑋𝑡 is the total per capita expenditure on the system of starchy staples given by 𝑋𝑡 = ∑𝑛𝑖=1 𝑝𝑖𝑡 𝑞𝑖𝑡 , where qit is the annual apparent per capita consumption of the 𝑖̇th starchy staple type at time t, and 𝑝𝑖𝑡 is the normalized annual real price for starchy staple type 𝑖 ̇ at time t. p is a vector of normalized real prices, a (p) is a function that is homogenous of degree one in prices, and lna(p) is specified as the translog equation: 𝑛 𝑛 𝑛 1 ln 𝑎(𝑝) = 𝛼0 + ∑ 𝛼𝑖 𝑙𝑛𝑝𝑖𝑡 + ∑ ∑ 𝛾𝑖𝑗 𝑙𝑛𝑝𝑖𝑡 𝑙𝑛𝑝𝑗𝑡 2 𝑖=1 (3 − 2) 𝑖=1 𝑗=1 Where i = 1…n denote commodities. The translog price index in equation (3-2) is non-linear, thereby posing some difficulties when aggregate annual time-series data are used. As a result, most studies employ a linear approximation to the non-linear price index. The most usual approximation to the translog aggregator function a(p) in the AIDS model has been the Stone price index suggested by Deaton and Muellbauer (1980). Moschini (1995), in the context of the AIDS, showed that employing Stone’s price index (ln 𝐏 ∗ = ∑𝑛𝑖=1 𝑤𝑖𝑡 𝑙𝑛𝑝𝑖𝑡 ) in place of a(p) can seriously bias elasticity estimates partly because this price index is influenced by changes in units of measurement. He therefore suggested using the following alternative price indices: the Törnqvist price index [log 𝑃𝑇 = 0.5 ∑𝑛𝑖=1(𝑤𝑖𝑡 + 𝑤𝑖𝑡0 )𝑙𝑜𝑔 (𝑃𝑖𝑡 ⁄𝑃𝑖𝑡0 )], the loglinear analogue of the Paasche price index–also known as the “corrected” Stone price index [log 𝑃 𝑠 = ∑𝑛𝑖=1 𝑤𝑖𝑡 𝑙𝑜𝑔 (𝑃𝑖𝑡 ⁄𝑃𝑖𝑡0 )], and the loglinear analogue of the Laspeyres price index [ln P 𝐋 = ∑𝑛𝑖=1 𝑤𝑖𝑡0 𝑙𝑛𝑝𝑖𝑡 ] , all of which are exact for a linearly homogeneous Cobb–Douglas aggregator function (Diewert 1976) and invariant to changes in units. 110 For the purpose of this study, the translog price aggregator, a(p), is approximated by the Laspeyres price index:ln P L = ∑𝑛𝑖=1 𝑤𝑖𝑡0 𝑙𝑛𝑝𝑖𝑡 , where 𝑤𝑖𝑡0 is the share of the ith commodity in the base period. Owing to its simplicity, LA-AIDS is very popular in empirical studies. The theoretical restrictions of homogeneity, adding up and symmetry are imposed on the parameters to ensure integrability of the demand system. Adding-up requires that expenditure shares sum to one (i.e., ∑𝑛𝑖=1 𝑤𝑖 = 1 ), and can be expressed in terms of model parameters as: 𝑛 𝑛 𝑛 ∑ 𝛼𝑖 = 0, ∑ 𝛽𝑖 = 0, ∑ 𝛾𝑖𝑗 = 0, 𝑖=1 𝑖=1 ∀𝑗 𝑖=1 An additional requirement for adding up is that 𝑛 ∑ 𝜃𝑖 = 0 𝑖=1 Hicksian demands are homogenous of degree zero in prices, which implies 𝑛 ∑ 𝛾𝑖𝑗 = 0 ∀𝑗 𝑗=1 The Slutsky symmetry restriction requires that 𝛾𝑖𝑗 = 𝛾𝑗𝑖 = 0 ∀ i, j These restrictions (adding-up, homogeneity, and symmetry) are imposed during estimation. Negativity is not automatically introduced, but by estimating all the compensated own-price elasticities one can test for their negativity. The expenditure elasticity, which varies depending on the type of good (normal or inferior), for good i̇ is given as: 𝜂𝑖 = 𝛽𝑖 +1 𝑤𝑖 (3 − 3) 111 In equation (3-3) parameter 𝛽𝑖 determines the effect of a change in total per capita starchystaple expenditure on the budget share of starchy-staple type 𝑖 ̇ and determines whether this good is normal or inferior. The Marshallian (uncompensated) own-price and cross-price elasticities are calculated in the following manner: 𝜀𝑖𝑗 = 𝛾𝑖𝑗 𝑤𝑖 − 𝛽𝑖 𝑤𝑖 𝑤𝑗0 − 𝛿𝑖𝑗 (3 – 4) Where 𝛿𝑖𝑗 is the Kronecker delta equaling 1 if i=j and 0 otherwise. In the LA-AIDS model the Hicksian or compensated price elasticities are derived using the Slutsky equation and are given by: ∗ 𝜀𝑖𝑗 = 𝜀𝑖𝑗 + 𝑤𝑗 𝜂𝑖 (3 − 5) It is well known that most economic time series data are very persistent, suggesting the possibility of non-stationary behavior. The presence of unit roots may invalidate the asymptotic distribution of estimators and influence elasticity estimates and their standard errors. Consequently, the appropriate model specification depends on the time-series properties of the data. The timeseries properties of the data are investigated to determine whether long-run relationships are economically meaningful or not. A formal test for unit roots is performed on all the data series used in the estimation. The unit roots test is first carried out with the pioneering Augmented DickeyFuller (ADF) test proposed in 1981. Wang and Tomek (2004) argue that the results of unit root tests are conditional on the remaining specification of the right hand side of the estimation equation — with and without a linear deterministic trend; and the length of lags, if any, to include. The tests 112 here were conducted with and without a trend and on the natural logarithm of deflated26 prices, the natural logarithm of starchy staples expenditure and the commodity budget shares. The number of lags included in the test was chosen so as to make the error term white noise. Due to the criticism of the ADF test – its low statistical power to reject a unit root, an alternative test–the Phillips-Perron (PP) test, proposed in 1988 and known for better finite sample properties than the ADF test—is also employed to check the robustness of the ADF results. The ADF and PP test for unit roots have nonstationarity as the null hypothesis. The difficulty of rejecting this hypothesis has been pointed in the literature. Hence to further test for the robustness of the ADF and PP results, the KPSS (Kwiatkowski, et al. 1992) test for unit roots that has stationarity as the null hypothesis is also applied. A similar unit roots testing approach is used in the data for the threee countries covered in this chapter. According to theory, regression of two variables that are integrated of order one I(1)27 but are not cointegrated results in a spurious regression. A cointegrating relationship exists when a linear combination of two or more I(1) variables results in residuals that are I(0)–implying that although the variables are non-stationary, a linear combination of them is stationary, thus generating an equilibrium relationship in the long-run. Karagiannis et al. (2000) observe that it is also possible to have a cointegrated regression even though the variables of interest have different time-series properties and thus, a different order of integration. According to the Granger representation theorem, a linear combination of series with a different orders of integration may still be a cointegrating regression. He notes further that if cointegration cannot be established for at least 26 27 Using the GDP deflator. Such that first-differencing makes the variables stationary. 113 one share equation, we cannot proceed further, and more likely a different functional specification may be used or the data set should be enlarged. Once the order of integration is determined, a simple test for cointegration that assumes a single cointegrating relationship is performed on the share equations given by: 𝑤𝑖𝑡 = 𝛼𝑖 + 𝜃𝑖 𝑆𝐻𝐴𝑅𝐸_𝑈𝑅𝐵𝑡 + ∑ 𝑋𝑡 𝛾𝑖𝑗 𝑙𝑛𝑝jit + 𝛽𝑖 𝑙𝑛 [ ] + 𝜀𝑖𝑡 𝑀 𝑗=1 𝑛 (3 − 6) All the variables in equation 3-6 are as defined in equation 3-1 and M is the price index linearized using Laspereyes formula. The test is conducted by estimating equation 3-6 separately for each starchy staple type by Ordinary Least Squares (OLS). The residuals from the OLS estimation are predicted. Using the PP regression28 and the Breusch-Pagan test for serial correlation, the number of lags that make the residuals white noise is determined. The Phillips-Perron unit root tests are applied on the residuals from the cointegrating regression. The null hypothesis is that the residuals have unit roots in them (no cointegration). Rejecting the null hypothesis implies the series is cointegrated. Once it is determined that all the variables are cointegrated, a dynamic Error Corrected Linearized Almost Ideal Demand System (ECLAIDS) is specified for starchy staples demand. Few studies employ formal testing procedures for unit-roots and cointegration needed to justify a dynamic specification for food demand systems (Balcombe and Davis, 1996; Karagiannis et al. 2000; and Nzuma and Sarker, 2008). The general approach followed in the dynamic specification of the demand system is conditioned on the view that there could be a long-run 28 Mainly because of its advantage over the ADF in small samples. 114 equilibrium cointegrating demand system measuring the long-run effects of prices and income on the demand for goods. New information and fluctuation in prices and income might disrupt the equilibrium, and the process of adjustment may be incomplete in any single period of time. In the period before these adjustments are completed, consumers will be ‘out of equilibrium,’ and their short-run responses to changes in prices and income may provide little guide as to their long-run effects. In modeling the dynamics in starchy staples consumption, this study uses Karagiannis et al. (2000) methodology for setting up an ECLAIDS. The approach entails estimating the system of linearized AIDS equations using the first-differenced variables and plugging in the first differenced lagged shares and the residuals obtained from the first step cointegrating regressions into each share equation to account for unit roots and cointegration. The ECLAIDS is specified as follows: ∆𝑤𝑖𝑡 = ∅𝑖 ∆𝑤𝑖𝑡−1 + 𝜃𝑖 ∆𝑆𝐻𝐴𝑅𝐸𝑈𝑅𝐵 𝑡 + 𝜏𝑖 𝑑1 + ∑ + 𝛽𝑖 ∆𝑙𝑛 [ 𝑛 𝑗=1 𝑋𝑡 ] + 𝜋𝑖 𝑣𝑖𝑡−1 + 𝜖𝑖𝑡 𝑎(𝒑) ∗ 𝛾𝑖𝑗 ∆𝑙𝑛𝑝𝑗𝑖𝑡 (3 − 7) In Equation (3-7), ∆ refers to the difference operator, 𝑣𝑖𝑡−1 are the estimated residuals from cointegration equations, and 𝜋𝑖 <0. Equation 3-7 is specified for starchy staples in Benin, Mali and Senegal and estimated using the iterative seemingly unrelated regression (ISUR) approach. The model is normalized to unity at the base period (2000) and all elasticities are evaluated at this point. As shown by Asche and Wessells (1997), there are no differences in formulas used to calculate price and expenditure elasticities between the AIDS and the linearized AIDS as long as calculations are made at the point of normalization. Consequently, the elasticity formula proposed by Chalfant (1987) correctly evaluates the elasticities of the ECLAIDS to equal those of the AIDS at the point of normalization. 115 3.5. Findings This section presents findings from the analysis of the determinants of aggregate demand for starchy staples in Senegal, Benin, and Mali. In particular, it provides estimates of the relationship between structural factors expected to influence consumption (urbanization and per capita incomes) as well as estimates of price and income elasticities of starchy staples demand for each major starchy staple type. The results are presented by country. 3.5.1. Determinants of Starchy Staples Demand – Senegal The analysis of trends in per capita food availability in Senegal (Chapter 2) revealed an overall decrease of 14 kg/year in the per capita availability of cereals and an increase in the supply of starchy roots and tubers (R&T) of about 18 kg/capita between the period 1980/85 and 2004/2009. A breakdown of the cereals and starchy R&T food groups by individual commodities revealed a growth in the per capita availability of rice and maize at the expense of millet and sorghum in the cereals food group. Cassava availability per capita also rose during the study period. However, it stayed relatively low compared to grains. This sub-section therefore aims to examine if there is any statistical relationship between above-mentioned descriptive trends and the factors hypothesized to influence aggregate level demand shifts (urbanization, relative prices, and growth in per capita incomes). In the absence of good time-series R&T price data, the analysis of the determinants of starchy staple demand in Senegal in this chapter is limited to cereals (rice, maize, millet, and sorghum). Table 3-1 presents summary statistics of the data used in estimating aggregate demand for Senegal. Average budget shares per starchy staple type in the study period were 48% for rice; 30% for millet; 12% for maize, and 10% for sorghum. The urban population share rose only by 3.64% in 116 the study period. The small variation in the urban population share is not very surprising because Dakar (the capital city of Senegal), which is the largest city in Senegal and characterized by rapid land occupation, may have reached its limits. The next largest cities in Senegal include Thiès and Kaolock, but these do not match up to Dakar in size/area and number of inhabitants. Table 3-1. Descriptive Summary of Variables in the Regression - Senegal: 1990-2009 Variable Mean Share urban 40.64 Lnprice 5.40 Lnpmil 5.08 Lnpsorg 5.04 Lnpmaize 5.11 lnX 10.14 Rice share 0.48 Millet share 0.30 Maize share 0.12 Sorghum share 0.10 Prices are log transformed deflated prices. Std. Dev. 1.11 0.15 0.13 0.15 0.11 0.14 0.07 0.09 0.05 0.02 Minimum 39.00 5.21 4.82 4.72 4.86 9.99 0.36 0.16 0.06 0.07 Maximum 42.64 5.77 5.37 5.30 5.36 10.46 0.60 0.46 0.25 0.15 Figure 3-1 also illustrates the trend in the share of individual cereals in total cereals budget over time. It is observed from the graphs that rice share in the cereals budget remained above 35% throughout the study period. Although the average share of millet in the study period was quite high, the graph illustrates a declining trend in the share of millet in the cereals budget over time. Prior to the year 2000, the share of maize in per capita cereal budget declined. However, the declining trend was reversed in the early 2000s. The graph of log-transformed deflated cereals prices (Figure 3-2) also shows fluctuations in cereals prices over time. 117 .2 .1 .15 Maize share .5 .45 .05 .35 .4 rice share .55 .6 .25 Figure 3-1. Shares in Cereals Budget - Senegal: 1990-2009 1995 2000 year 2005 1990 1995 2000 year 2005 2010 1995 2000 year 2005 2010 1990 1995 2000 year 2005 2010 .06 .08 .1 .12 Sorghum share .4 .3 .2 .1 2010 Source: Author. Budget shares were computed using cereal availability (kg/capita/year) data from FAO’s Food Balance Sheet and price data from Senegal’s Agricultural Market Information System. 5 5.2 5.4 5.6 5.8 Figure 3-2. Natural Logarithm of Deflated Cereals Prices - Senegal: 1990-2009 4.8 Millet Share 1990 .14 .5 1990 1990 1995 2000 Year Rice Sorghum 2005 2010 Millet Maize Capital City Market-Senegal (Dakar) Source: Author, using price data from Senegal’s Agricultural Market Information System. 118 An examination of the correlation coefficient between the urban population share and starchy staples budget shares reveals a strong positive relationship with the rice budget share (0.78) and with the maize budget share (0.71). Millet and sorghum on the other hand were found to be negatively correlated with the urban population share with correlation coefficients of -0.92 and 0.34 respectively. These relationships are not surprising because millet is a basic rural food in Senegal, although over time, rice has deeply penetrated rural markets and diets. The results of the ADF and PP test for non-stationarity of the variables in the demand estimation are reported in Table A3-1 in Appendix (case with trend) and Table A3-2 in Appendix (the case without trend). In both cases, results suggest most variables are stationary and few are non-stationary in levels. First differencing also fails to make all the variables stationary when the ADF test is applied in the case with and without trend. Based on a PP test, a unit root is rejected at a 5% significance level for some of the variables in the case with and without a trend. Performing the PP-test on first-differenced variables, non-stationarity is rejected at a 1% level of significance for all the variables in the case with and without trend.29 Using the KPSS test for unit roots (Appendix, Tables A3-3 and A3-4), we reject the null of stationarity in some of the variables to be used in the demand estimation in the case with and without trend. When all the variables are treated as nonstationary in levels and first differenced, we do not reject stationarity in the case with and without trend in all the variables to be used in the estimation. Thus, in all three tests we do not reject stationarity in some of the variables in levels. The inconclusive result of the unit root tests on the variables in levels supports existing arguments on the low power of unit root tests in small samples. 29 Since a trend in levels becomes a constant in first differences, no trend needs to be included here, making the option of first differencing with no trend more appropriate. 119 In the absence of any reasons why in the same market some prices would be generated by a unit process and others are not, and also given that the consequences of ignoring the stochastic properties of the data are likely to be severe, the demand analysis is carried out assuming nonstationarity in prices in levels. A dynamic model which corrects for non-stationarity is specified. Table 3-2 contains the results of the unit roots test on the residuals from the cointegrating regression (𝑣𝑖𝑡−1 ). We reject unit roots in the residuals from each equation in the case without trend at a 5% level in three out of the four regressions– i.e., the residuals are stationary with a long-run equilibrium relationship between the dependent variables (the shares) and a linear combination of the independent variables. In the case with trend, we reject unit roots in two of the four share equations. Table 3-2. Tests of Regression Residuals for Unit Roots - Senegal Equation With Trend Without Trend T-Stat.(rh0) T-Stat. (t) p-value T-Stat.(rh0) T-Stat. p-value Rice Share -11.732 -2.724 0.2261 -11.82 -2.787 (t) 0.0601 Maize Share -13.363 -2.978 0.1385 -13.39 -3.062 0.0295 Millet Share -20.643 -4.706 0.0007 -20.841 -4.852 0.0000 Sorghum Share -20.885 -4.289 0.0033 -20.975 -4.443 0.0002 1% 5% 10% PP test (t)-Trend -4.380 -3.600 -3.240 PP test (rho)- Trend -22.500 -17.900 -15.600 PP test (t)- No Trend -3.750 -3.000 -2.630 PP test (rho)-No -17.200 -12.500 -10.200 Critical values Null Hypothesis: Residuals are non-stationary – i.e., unit roots (no cointegration). Trend 120 Having established the existence of a long run equilibrium relationship, an ECLAIDS model (equation 3-7) is estimated for the four major grain types (rice, maize, millet, and sorghum) consumed in Senegal. The model was estimated with and without the dummy variable that captures the effect of any structural change in consumption habits due to devaluation. The inclusion of the dummy variable failed to provide any noticeable improvement in the estimated parameters. As a result, the reported parameter estimates are from the model without the dummy for devaluation. Table 3-3 contains the estimated parameters of the ECLAIDS for cereals demand in Senegal 19902009. The estimated parameters of the error correction terms (𝜋𝑖 ) are all statistically significant and have the correct signs, indicating that deviations from long-run equilibrium are corrected within the time period. It is also worth noting that the significance of the error correction terms in SUR estimates is consistent with the previously obtained results of cointegration analysis. The estimated R-squares are 74% for rice, 72% for millet, and 30% for sorghum. Furthermore, the log of per capita starchy staples expenditure and the urban population share are not statistically significant in any of the budget share equations, meaning that starchy staples expenditure behavior as well as the urban population shares are influenced neither by changes in aggregate expenditures on starchy staples per capita or growth in urban population shares when aggregate consumption data are considered. However, this may be an inappropriate conclusion given that the distribution of income across different consumers and/or by place of residence may be a more critical determinant of cereals consumption than national level per capita expenditures. Furthermore, the urban population did not change much (increased by 3.64%) in Senegal during the study period. This may explain why urbanization is not statistically significant in the starchy staple demand model. As shown by Asche and Wessells (1997), there are no differences in formulas used to calculate price and expenditure elasticities between the AIDS and the linearized AIDS as long as 121 calculations are made at the point of normalization. Consequently, the elasticity formula proposed by Chalfant (1987) correctly evaluates the elasticities of the ECLAIDS to equal those of the AIDS at the point of normalization (Nzuma and Sarker, 2008). The model (equation 3-7) is normalized to unity at the base period (2000) and all elasticities are evaluated at this point. The short-run Marshallian price elasticities are measured as in equation 3-4 and the expenditure elasticities are measured as in equation 3-3 and using the estimated ECLAIDS parameters from equation (3-7). The Hicksian short run elasticities are then obtained through Slutsky equation as in equation 3-5. The short-run ECLAIDS parameter estimates are also used to compute their long-run counterparts using the partial adjustment formulation proposed by Johnson et al. (1992). 122 Table 3-3. Parameter Estimates from Error-Corrected Linear AIDS Model - Senegal driceshare Variables Coef. D1.lriceshare D1.lmilshare D1.lsorgshare share_urban D1.lnprice D1.lnpmil D1.lnpmaize D1.lnpsorg Dln(X/P) -0.060 0.000 0.278 -0.259 0.006 -0.010 -0.232 -0.490 -0.002 𝝅𝒓𝒊𝒄𝒆 𝝅𝒎𝒊𝒍𝒍𝒆𝒕 𝝅𝒔𝒐𝒓𝒈𝒉𝒖𝒎 Constant Source: Author. dmilshare Std. Err. 0.115 0.006 0.043 0.044 0.054 0.016 0.127 0.171 0.244 dsorgshare P>|z| Coef. Std. Err. P>|z| 0.604 0.978 0.000 0.000 0.909 0.548 0.067 0.004 0.992 0.128 -0.003 -0.259 0.457 -0.175 -0.099 0.266 -0.843 0.109 0.103 0.006 0.044 0.069 0.058 0.023 0.143 0.186 0.256 0.216 0.652 0.000 0.000 0.003 0.000 0.062 0.000 0.669 123 Coef. 0.638 -0.002 -0.010 -0.099 0.152 0.054 -0.005 -1.321 0.089 Std. Err. 0.195 0.005 0.016 0.023 0.047 0.011 0.103 0.326 0.202 P>|z| 0.001 0.661 0.548 0.000 0.001 0.000 0.961 0.000 0.661 Thus, the long-run estimates equal the negative of the short-run estimates (equation 3-7) divided by the EC term’s parameter (- β0/𝜋𝑖 ). Similarly, the long-run elasticities are measured using the formulas in equation (3-3 to 3-5) and the long-run parameter estimates. The estimated short-run and long-run elasticities are reported in Table 3-4 and Table 3-5 respectively. The short-run expenditure elasticity for millet is greater than one and significant at a 1% level. This indicates luxury good-like behavior for millet. Rice is short-run expenditure inelastic, making rice a necessity in the short-run. In the long run, only the expenditure elasticity for millet is significant at a 5% level and millet continues to behave as a luxury good in the long-run. Table 3-4. Estimated Error-Corrected Short-Run Demand Elasticities - Senegal Commodity Rice Millet Sorghum Expenditure Elasticities 0.587* 1.927* 0.943 Uncompensated Price Elasticities lnprice -0.272 -1.423* -0.075 lnpmil -0.344* 0.328 -1.094* lnpsorghum 0.020 -0.428* -0.386** lnpmaize 0.037 -0.668* 1.710* Compensated Price Elasticities lnprice 0.057 -0.342** 0.454** lnpmil -0.175** 0.880* -0.823* lnpsorghum 0.072** -0.256* -0.302** lnpmaize 0.074 -0.547* 1.769* Source: AuthorSignificant at 1% (*); 5% (**); and 10% (***) 124 Maize 0.539 0.357 -2.641* 2.454* -0.709 0.659 -2.487* 2.503* -0.675 Table 3-5. Senegal: Estimated Error-Corrected Long-Run Demand Elasticities Commodity lnprice lnpmil lnpsorghum lnpmaize Rice Millet Sorghum Expenditure Elasticities 0.157 2.099* 0.957 Uncompensated Price Elasticities 0.485 -1.687* -0.057 -0.701* 0.575 -0.828** 0.040 -0.507* -0.536* 0.076 -0.792** 1.294* Compensated Price Elasticities 0.573 -0.510*** 0.480* -0.656*** 1.177** -0.553*** 0.054 -0.320** -0.450* 0.086 -0.660** 1.354* lnprice lnpmil lnpsorghum lnpmaize Source: Author Note: Significant at 1% (*); 5% (**); and 10% (***) Maize 3.556 -1.233 -4.023** 1.598** 0.101 0.761 -3.002** 1.916* 0.326 With the exception of millet, all the short-run own-price Marshallian elasticities are negative, and thus the corresponding demand curves are downward sloping (see Table 3.4). However, only the uncompensated short-run own-price elasticity of sorghum is statistically significant at a 5%, and sorghum is found to be own-price inelastic in the short-run. When the longrun own-price Marshallian elasticities are considered, sorghum remains price inelastic and statistically significant, with long-run Marshallian own-price elasticity greater than the short-run. Not all short-run own-price Hicksian elasticities are negative as expected. The positive and statistically significant compensated demand curves for millet in both the short-run and the long-run are not theoretically reasonable, and therefore warrant further investigation. The short-run Hicksian cross-price elasticities (Table 3-4) reveal a relationship of complementarity between millet and rice in the short-run; and a relationship of substitution between sorghum and rice in the short-run, and these relationships are statistically significant at a 5% level. For instance, in the short-run, a 1% increase in the price of sorghum will result in a compensated 125 increase in rice consumption of 0.072%, while an increase in the price of millet will decrease rice consumption by 0.175%. The finding in earlier studies (Delgado and Reardon, 1992; Kennedy and Reardon, 1994) that rice is a substitute for coarse grains (millet and sorghum) and vice versa is supported only in the case of sorghum in the short-run. This relationship of complementarity between millet and rice; and substitution between sorghum and rice is maintained in the long-run. However, only the former remains statistically significant. Also in the short-run, sorghum and millet have a relationship of complementarity, and maize and millet are complements with statistically significant compensated short-run cross-price elasticities of -0.256 and -0.547 respectively. Still in the short run, maize is a substitute for sorghum (1.769) and the relationships are statistically significant at 1% level. The descriptive analysis of the trend in per capita cereals consumption (Chapter 2) and the graphical examination of trend in the share of specific cereals type in the per capita cereals budget discussed earlier in this chapter both revealed that per capita consumption of maize and the share of maize in the cereal budget in Senegal increased in the study period. Millet and sorghum on the other hand experienced declining per capita consumption and declining shares. The findings from the statistical analysis support the substitution of maize for sorghum seen in the descriptive analysis (see also Taoundyande and Yade, 2012). However, the relationship of complementarity between maize and millet seen in the statistical analysis does not correspond with the opposite trend seen in the descriptive analysis. Contrary to the short-run, the compensated cross-price relationship between sorghum and rice is not statistically significant in the long-run. All other cross-price relationships in the short-run are maintained in the long-run. To conclude for Senegal, the results of the error-corrected demand model also provide evidence of substitution between rice and sorghum as hypothesized. However, the relationship of 126 complementarity between rice and millet in both the short-run and long-run are contrary to findings from earlier studies that rice is a substitute for coarse grains. Hence, the hypothesis that rice is a substitute for coarse grains (millet and sorghum) is only partially accepted in Senegal. The dynamic specification (long-run and short-run) of cereals demand in Senegal provide evidence of substitution of maize for sorghum and complementarity between maize and millet. Rice and maize have the same behavior towards millet and sorghum. The finding that millet is expenditure elastic is contrary to the expectation that as per capita income (and hence the budget share allocated to starchy staples) increases, the share of the budget allocated to coarse grains will decrease and that to rice will increase. 3.5.2. Determinants of Starchy Staples Demand – Benin Table 3-6 contains a descriptive summary of the data used to estimate aggregate demand of starchy staples for Benin. Millet and sorghum combined represent less than 5% of the starchy staple food budget. As a result, due to small size of the sample and also to avoid degrees of freedom problems, both were left out of the analysis of starchy staples demand in Benin. Starchy staples for Benin in this chapter include rice, maize, yams, and cassava. Cassava alone represents an average of 53% of the starchy staple budget, yams represent 30%, rice30 represents 4%; and maize represents 14%. 30 Imported rice prices are used since almost all of the rice available for consumption in Benin comes from imports. 127 Table 3-6. Benin - Descriptive Statistics of Variables in the Regression, 1990-2009 Variable Mean Std. Dev. Share urban 38.15 2.11 lnprice 5.76 0.10 lnpmaize 4.90 0.25 lnpcassava 4.80 0.55 lnpyams 4.77 0.18 lnX 10.83 0.20 rice share 0.04 0.01 maize share 0.14 0.04 yams share 0.30 0.08 cassava share 0.53 0.11 Source: Author. Prices are log transformed deflated prices. Minimum Maximum 34.50 41.60 5.60 5.98 4.50 5.25 4.14 5.75 4.41 5.01 10.43 11.19 0.02 0.06 0.07 0.20 0.15 0.43 0.39 0.74 Figure 3-3 shows time series of the share of individual starchy staple types in total per capita starchy staples budget. The share of rice in starchy staples expenditures fluctuated between 2 and 6% in the study period. The upward movement experienced between 1999 and 2005 changed to a decline between 2005 and 2007. Since 2007, the share of rice has been on the rise, and this period corresponds to the period of much higher world rice prices. The share of maize was between 7 and 20% in the study period, and in spite of the drop between 2005 and 2007, it increased in 2008 and 2009. In the study period, the share of cassava in per capita starchy staples budget was above 40%. However, since 2007, the share of yams has slowly increased (but remained less than 30%) while that of cassava dropped but stayed above 50%. The graph of the logarithm transformed deflated starchy staples prices (Figure 3-4) also shows huge fluctuations in starchy staples prices over time. 128 .1 .15 Maize share .04 .03 .05 .02 Rice share .05 .2 .06 Figure 3-3. Shares in Starchy Staples Budget - Benin: 1990-2009 2000 year 2005 1990 1995 2000 year 2005 2010 1995 2000 year 2005 2010 1990 1995 2000 year 2005 2010 .7 .4 .5 .6 Cassava share .4 .3 .2 .1 2010 Source: Author. Budget shares were computed using cereal availability (kg/capita/year) data from FAO’s Food Balance Sheet and price data from Benin’s Agricultural Market Information System. 0 .5 1 1.5 Figure 3-4. Logarithm Transformed Deflated Starchy Staples Prices - Benin: 1990-2009 -.5 Yams share 1990 .8 1995 .5 1990 1990 1995 2000 Year Rice Cassava 2005 2010 Yams Maize Capital City Market-Dantokpa-Benin Source: Author, using price data from Benin’s Agricultural Market Information System. 129 An examination of the correlation coefficient between the urban population share and starchy staples consumption shares reveals a positive relationship between the yam budget share and the urban population share (0.29); and the rice budget share and the urban population share (0.28). Cassava and maize budget shares, on the other hand, were found to be correlated negatively, with the urban population share with correlation coefficients of -0.23 and -0.16 respectively. Formal investigation of unit roots was also performed using the ADF, the PP and the KPSS tests. Tables A3-5 and A3-6 in Appendix contain the results of the ADF and PP tests for unit roots. The results of the ADF test for unit roots with and without trend provide evidence of nonstationarity in all the variables to be used in the demand estimation. While in the case without trend, first differencing makes all the variables stationary (at the 5% significance level), in the case with trend, first differencing fails to make all the variables stationary. Applying the PP-test for unit roots, we reject stationarity in all the variables in the case without trend and fail to reject stationarity in one out of the nine variables in the case with trend. First differencing with and without trend with the PP-test makes all the variables stationary at a 5% significance level. The KPSS test for unit roots was also performed using the same lag structure as in the ADF and PP tests. In the case with and without trend (Table A3-7 and A3-8 in Appendix) we reject stationarity at a 5% significance level in some of the variables. Applying the test to first-differenced variables, we do not reject the null of stationarity in all the variables in the case with and without trend. Thus, with respect to stationarity, we reach the same conclusion as for Senegal, and the model is estimated handling the stochastic properties of the data. To proceed with the dynamic specification of starchy staples demand in Benin, a test for cointegration in the regression residuals is carried out to determine if there is a long-run equilibrium relationship between the variables in the demand equations. The results of the test are presented in 130 Table 3-7. In the case with trend, we reject the null of unit roots (no cointegration) in two of the four equations. In the case without trend, we reject the null of no cointegration in three of the four regressions at a 5% level of significance and in one regression at a 10% level of significance. Table 3-7. Tests of Regression Residuals for Unit Roots – Benin Equation With Trend Without Trend T-Stat.(rh0) T-Stat. (t) p-value Rice Share -10.561 -2.47 0.3432 -10.702 -2.577 0.0978 Maize Share -12.358 -2.747 0.217 -12.394 -2.835 0.0534 Yams Share -18.629 -3.891 0.0125 -18.666 -4.016 0.0013 Cassava Share -21.338 -4.511 0.0015 -21.391 -4.667 0.0001 Critical values TStat.(rh0) T-Stat. (t) p-value 1% 5% 10% PP test (t)-Trend -4.380 -3.600 -3.240 PP test (rho)- Trend -22.500 -17.900 -15.600 PP test (t)- No Trend -3.750 -3.000 -2.630 PP test (rho)-No Trend -17.200 -12.500 -10.200 Null Hypothesis: Residuals are non-stationary – i.e., unit roots (no cointegration). Having established the existence of a long-run equilibrium relationship, the dynamic specification as in equation 3-7 is used to measure the long-run effects of prices and income on the demand for starchy staples in Benin. As was the case in Senegal, the dummy variable for devaluation is not statistically significant in all share equations. Table 3-8 contains the estimated parameters from the ECLAIDS model for starchy staples in Benin. The relationship between urban population share and starchy staples demand is not statistically significant in all three share equations. The lagged residuals from the cointegrating regression have the appropriate sign (negative), and are significant in all three share equation regressions. The coefficient of the log of 131 per capita starchy staples budget is not statistically significant in all three regressions. Most of the coefficients of prices are statistically significant at 1% level. Table 3-9 and Table 3-10 report the estimated short-run and long-run elasticities from the dynamic demand specification for starchy staples in Benin. Only the estimates of the expenditure elasticities for maize and cassava are statistically significant at a 5% level. The estimates reveal that maize and cassava are expenditure elastic in the short-run, such that an increase in per capita starchy staple budget would result in a more than proportionate increase in expenditure on these commodities. The short-run Marshallian own-price elasticities are negative and statistically significant at a 1% level for maize, cassava, and yams, indicating that an increase in the price of any of these commodities would result in a decrease in its expenditure. The uncompensated own-price elasticity for rice, on the other hand, is positive but not significant at a 5% level. The compensated own-price elasticities are negative for yams and maize and these are also statistically significant at a 1% level. Overall, the demand for all of these starchy staples appears to be price-inelastic as expected. Furthermore, the cross-price compensated short-run elasticities reveal that maize is a substitute for yams in the short run – a 1% increase in the price of maize will result in a 0.095% increase in yam expenditures. All other short-run compensated cross-price relationships are not statistically significant. In the long-run, only the expenditure elasticity for cassava is statistically significant at a 1% level. All uncompensated own-price elasticities are not statistically significant in the long-run. The compensated own price elasticity for maize is negative and statistically significant. All compensated cross-price relationships are not statistically significant in the longrun. 132 Table 3-8. Parameter Estimates in ECLAIDS for Starchy Staples in Benin D1.lcasshare D1.lyamshare D1.lmaizehare share_urban D1.lnprice D1.lnpyams D1.lnpcass D1.lnpmaize D1.ln(X/P) 𝝅𝒄𝒂𝒔𝒔 𝝅𝒚𝒂𝒎𝒔 𝛑𝐦𝐚𝐢𝐳𝐞 Constant Source: Author. Coef. 0.009 0.000 -0.015 -0.124 0.212 -0.074 0.108 -0.753 -0.007 Cassava Std. Err. 0.044 0.004 0.006 0.022 0.021 0.009 0.167 0.161 0.139 P>|z| 0.837 0.968 0.013 0.000 0.000 0.000 0.519 0.000 0.961 Coef. 0.029 Yams Std. Err. 0.064 P>|z| 0.644 0.001 -0.007 0.162 -0.124 -0.032 -0.119 -0.708 -0.034 0.004 0.011 0.028 0.022 0.011 0.178 0.163 0.150 0.813 0.531 0.000 0.000 0.004 0.502 0.000 0.818 133 Coef. -0.051 Maize Std. Err. 0.054 P>|z| 0.349 -0.002 -0.005 -0.032 -0.074 0.110 0.047 - 0.002 0.007 0.011 0.009 0.010 0.072 - 0.183 0.451 0.004 0.000 0.000 0.516 - -0.368 0.081 0.169 0.062 0.030 0.186 Table 3-9. Estimated Error-Corrected Short-Run Demand Elasticities - Benin Commodity lnpyams lnpmaize lnpcassava lnprice Yams Maize Cassava Expenditure Elasticities 0.689 1.265* 1.262* Uncompensated Price Elasticities -0.458* -0.280** -0.401* -0.027 -0.426* -0.226* -0.194 -0.523** -0.592* -0.009 -0.036 -0.043** Compensated Price Elasticities -0.193* 0.205* 0.083 0.095* -0.201* -0.001 0.089 -0.003 -0.074 0.009 -0.001 -0.008 Rice -0.292 0.243 0.043 -0.007 0.013 lnpyams lnpmaize lnpcassava lnprice Source: Author. Note: Significant at 1% (*); 5% (**); and 10% (***) 0.131 -0.009 -0.127 0.005 Table 3-10. Estimated Error-Corrected Long-Run Demand Elasticities - Benin Commodity lnpyams lnpmaize lnpcassava lnprice Yams Maize Cassava Expenditure Elasticities 0.561 1.721 1.348* Uncompensated Price Elasticities -0.235 -0.763 -0.533** -0.039 0.563 -0.300* -0.274 -1.423** -0.458 -0.013 -0.098 -0.057*** Compensated Price Elasticities -0.019 -0.102 -0.016 0.061 -2.513* -0.060 -0.043 -0.715 0.096 0.002 -0.051 -0.020 lnpyams lnpmaize lnpcassava lnprice Source: Author. Note: Significant at 1% (*); 5% (**); and 10% (***) 134 Rice -2.751 1.083 0.160 0.827 0.682 0.027 -0.329 -0.304 0.607 Overall for Benin, we observe the relationship between urban population share and starchy staples demand is not statistically significant in any of the share equations. However, the compensated cross-price relationship of substitution between maize and yams is maintained in the short-run, while all other compensated cross-price relationships continue to be statistically insignificant. A possible explanation for the substitution relationship between maize and yams is that both are used to make “fufu”, a basic carbohydrate main dish eaten with sauce. All compensated cross-price relationships are not statistically significant in the long-run. A possible explanation for the bizarre results for rice in Benin is due to the large unrecorded trade in rice between Benin and Nigeria, which has banned polished rice imports. Furthermore, given the erratic nature of Nigeria’s trade policies over the year, the rice figures for Benin are not inflated by a uniform amount across all years. Allen et al. (2011) outlines the details of the problems of using FBS data for Benin. 3.5.3. Determinants of Starchy Staples Demand – Mali Descriptive statistics for the data used in examining starchy staples demand in Mali are presented in Table 3-11. The budget shares are 20% for rice, 36% for millet, 30% for sorghum, and 14% for maize. The average urban population share in the study period ranged from 23.3% to 32.7%. Figure 3-5 also shows the trend in the budget share allocated to individual cereal types in Mali. The share of sorghum in the cereals budget declined in the study period while that of maize has been on the rise. Millet occupied the largest share in per capita cereals expenditures. However, its share has been fluctuating over time. 135 Table 3-11. Descriptive Statistics of Variables in the Regression - Mali: 1990-2009 Variable Mean Std. Dev. Share urban 27.80 2.94 lnprice 5.61 0.11 lnpmillet 4.94 0.22 lnpsorghum 4.90 0.22 lnpmaize 4.87 0.18 lnX 10.32 0.17 Rice share 0.20 0.04 Maize share 0.14 0.02 Millet share 0.36 0.03 Sorghum share 0.30 0.05 Source: Author. Prices are log transformed deflated prices Min 23.30 5.46 4.52 4.44 4.47 9.86 0.11 0.09 0.31 0.24 Max 32.74 5.89 5.35 5.33 5.20 10.58 0.28 0.18 0.42 0.38 Maize share .25 .2 .08 .1 .15 .1 Rice share .3 .12 .14 .16 .18 Figure 3-5. Shares in Cereals Budget - Mali: 1990-2009 1995 2000 year 2005 1990 1995 2000 year 2005 2010 1995 2000 year 2005 2010 1990 1995 2000 year 2005 2010 .35 .2 .25 .3 Sorghum share .4 .32 .34 .36 .38 Millet share 1990 .4 .42 1990 2010 Source: Author. Budget shares were computed using cereal availability (kg/capita/year) data from FAO’s Food Balance Sheet and price data from Mali’s Observatoire du Marché Agricole (OMA). 136 An examination of the correlation coefficients between the urban population share and budget shares reveals that rice and maize budget shares are positively related to the urban population share, with correlation coefficients of 0.62 and 0.80 respectively. The sorghum budget share is negatively related with the urban population share, while there is almost nil association between the millet budget share and the urban population share. The graph of the logarithm of deflated prices for cereals in Mali is displayed in Figure 3-6 and it illustrates that rice prices have been generally higher than the prices of all the other cereals, and also that millet, maize and sorghum prices have tended to move closely together in the same direction. 4.5 5 5.5 6 Figure 3-6. Logarithm Transformed Deflated Cereals Prices - Mali: 1990-2009 1990 1995 2000 Year Rice Sorghum 2005 2010 Millet Maize Capital City Market-Mali (Niarela,Bamako) Source: Author, using price data from Mali’s Observatoire du Marché Agricole (OMA). Note: Prices are log transformed deflated prices 137 Tables A3-9 and A3-10 in Appendix contains the results of the ADF and PP test for unit roots. The results reveal that in the case with and without trend, seven of the nine variables are stationary in levels. First differencing also makes all the variables stationary in the case with and without trend using the ADF test. Applying the PP-test for unit roots, we find that evidence of non-stationarity is still mixed in the case with and without trend–two of the nine variables have unit roots in them in levels. First differencing with and without trend makes all the variables stationary. The KPSS test for unit roots also provides mixed evidence of non-stationarity in levels. But, first differencing in the case with and without trend makes all the variables stationary (Appendix, Tables A3-11 and A3-12). As was in the case with Senegal and Benin, mixed evidence of non-stationarity in the levels led to the estimation of the ECLAIDS model for starchy staples demand for Mali. The test for cointegration (Table 3-12) in the regression residuals reveal that in the case with and without trend, we reject unit roots (no cointegration), thus indicating that there is a long run equilibrium relationship between the variables in the demand system. Following Karagiannis et al. (2000), a dynamic model for starchy staples demand in Mali is specified as in equation 3-7. 138 Table 3-12. Mali-Tests of Regression Residuals for Unit Roots Equation With Trend T-Stat.(rh0) Rice Share -17.962 T-Stat. (t) -3.746 Maize Share -15.703 Millet Share Sorghum Share Without Trend 0.0195 -18.026 T-Stat. (t) -3.887 -3.566 0.0328 -15.719 -3.717 0.0039 -15.213 -5.119 0.0001 -15.77 -4.998 0.000 -14.715 -3.156 0.0935 -14.61 -3.223 0.0187 Critical values p-value T-Stat.(rh0) p-value 0.0021 1% 5% 10% PP test (t)-Trend -4.380 -3.600 -3.240 PP test (rho)- Trend -22.500 -17.900 -15.600 PP test (t)- No Trend -3.750 -3.000 -2.630 PP test (rho)-No Trend -17.200 -12.500 -10.200 Source: Author. Note: Null Hypothesis: Residuals are non-stationary – i.e., unit roots (no Cointegration). Table 3-13 shows the parameters estimated from a dynamic specification of starchy staples demand in Mali. The coefficient on the urban population share is positive and statistically significant at a 5% level only for millet. However, the effect of urbanization on shifts in millet expenditures seems to be small in magnitude. 139 Table 3-13. Parameter Estimates from Error-Corrected Linear AIDS model - Mali Variables D1.lriceshare D1.lmilshare D1.lsorgshare share_urban D1.lnprice D1.lnpmil D1.lnpmaize D1.lnpsorg Dln(X/P) 𝝅𝒓𝒊𝒄𝒆 𝝅𝒎𝒊𝒍𝒍𝒆𝒕 𝝅𝒔𝒐𝒓𝒈𝒉𝒖𝒎 Constant Source: Author. Coef. 0.307 0.000 0.045 -0.147 0.008 0.051 -0.491 -1.476 -0.001 Rice Share Std. Err. 0.062 0.002 0.058 0.034 0.033 0.039 0.165 0.175 0.061 P>|z| 0.000 0.879 0.437 0.000 0.803 0.192 0.003 0.000 0.991 Coef. Millet Std. Err. P>|z| 0.248 0.085 0.004 0.002 -0.147 0.277 -0.127 -0.065 0.159 -1.257 -0.070 140 0.001 0.034 0.041 0.023 0.033 0.085 0.174 0.030 0.023 0.000 0.000 0.000 0.047 0.062 0.000 0.018 Coef. Sorghum Std. Err. P>|z| 0.520 -0.002 0.051 -0.065 0.066 0.007 0.235 -1.580 0.039 0.098 0.002 0.039 0.033 0.030 0.032 0.171 0.159 0.062 0.000 0.482 0.192 0.047 0.025 0.824 0.169 0.000 0.535 The relationship between urban population share and rice and sorghum are not statistically significant. The lagged residuals from the cointegrating regressions are negative in all three share equations but only statistically significant in the rice and millet share equations. Per capita starchy staples expenditures are also statistically significant in the rice share equation and in the millet equation. Tables 3-14 and 3-15 show the estimated short-run and long-run elasticities from the starchy staples demand model for Mali. The short-run expenditure elasticities are statistically significant at a 1% level and also greater than unity for millet, sorghum and maize, indicating these cereals are expenditure elastic. The same story is preserved in the long-run (Table 3-15). All the own-price uncompensated price elasticities exhibit the expected negative sign and are statistically significant in the short-run and in the long-run. Rice, sorghum, and maize also exhibit a downward sloping compensated demand curve in the short-run and long-run. The short-run compensated cross-price elasticities reveal that maize is a substitute for rice and sorghum, rice is a substitute for sorghum, and maize is a complement to millet. In the long-run all compensated cross-price relationships are that of substitution, with the exception of maize and millet that are complements, and millet and sorghum, and rice and millet with no statistically significant long-run relationship. 141 Table 3-14. Mali: Estimated Error-Corrected Short-Run Demand Elasticities Commodity Rice Millet Sorghum Expenditure Elasticities -0.729 1.478* 1.957* Uncompensated Price Elasticities -0.349* -0.579* -0.065 0.057 -0.323** -0.583** 0.604 -0.314** -1.206* 0.268*** -0.450* 0.138 Compensated Price Elasticities -0.557* -0.159 0.491* -0.185 0.167 0.067 0.425* 0.049 -0.725* 0.167 -0.246* 0.409* lnprice lnpmil lnpsorghum lnpmaize lnprice lnpmil lnpsorghum lnpmaize Source: Author. Note: Significant at 1% (*); 5% (**); and 10% (***) Maize 1.709* -0.142 -1.158* 0.307 -0.716* 0.344 -0.590* 0.726 -0.480* Table 3-15. Mali: Estimated Error-Corrected Long-Run Demand Elasticities Commodity lnprice lnpmil lnpsorghum lnpmaize lnprice lnpmil lnpsorghum lnpmaize Rice Millet Sorghum Expenditure Elasticities -0.172 1.380* 1.605* Uncompensated Price Elasticities -0.559* -0.460* -0.041 0.039 -0.462* -0.369** 0.409* -0.250** -1.130* 0.181 -0.358* 0.088 Compensated Price Elasticities -0.608* -0.068 0.415* -0.018 -0.003 0.164*** 0.367* 0.089 -0.736* 0.158** -0.167** 0.309* Source: Author. Note: Significant at 1% (*); 5% (**); and 10% (***) 142 Maize 1.421* -0.079 -0.873* 0.201 -0.669* 0.324** -0.402** 0.550* -0.473* 3.6. Chapter Summary The main objective of the preceding analysis was to examine the aggregate-level determinants of starchy staples demand in Benin, Mali and Senegal. An Error Corrected linearized Almost Ideal demand system (ECLAIDS) was specified following the results of the test for the stochastic properties of the data (unit roots and cointegration). A specific goal of the analysis was to determine any statistical association between the growth in urban population share and the demand for traditional coarse grains such as millet and sorghum. Although domestic price trends are not strictly uniform across all three countries, on the whole similar trends could be observed in all three countries for rice prices relative to coarse grains. Common to Mali and Senegal in the Sahel region of WA is an increasing trend in the share of maize and rice and a declining trend in the share of millet and sorghum in the starchy staples budget over time. In Benin, the shares of individual starchy staple types in the starchy staple budget in the period 1990-2009 have been fluctuating, not exhibiting any noticeable trend. The analysis of cereals demand after correcting for the unit root properties of the data does not provide any support for a statistical association between the urban population share and cereals consumption behavior in Senegal, but points to a statistically significant, but small, relationship between millet and urban population share in Mali. A principal channel31 through which urbanization affects consumption is by increasing per capita incomes. By including per capita expenditures on starchy staples as a separate variable in the estimated model, the model specification already controls for per capita expenditure. However, while the coefficient of urbanization and per capita expenditures picks up the individual effects of each of these 31 Other channels include changes in lifestyle, for instance increased female employment outside their homes. 143 variables, both variables could interact to generate additional effects on consumption. The insignificance of the urbanization variable in the dynamic specification could be the result of the way in which the variable is introduced into the model. Ideally, one would like to add an interaction term between the urban population share and starchy staples expenditures. However, due to the small number of observations, additional terms will pose degrees of freedom problems, making it impossible to estimate the model. The manner in which the urban population share is incorporated in this study is therefore the most straightforward given starchy staples price data limitations. As discussed in Chapter 1, evidence on the role of relative cereals prices in influencing cereals consumption in West Africa has been mixed. It has been argued that changes in rice consumption, for instance, are more linked to structural factors like urbanization and to a lesser extent short-term price changes. The Hicksian cross-price elasticities from the error-corrected demand model provide evidence of a statistically significant relationship of substitution in the short-run and long-run between rice and sorghum as hypothesized for Mali and Senegal. While in Senegal, rice is found to be a complement to millet in both the short-run and in the long-run, in Mali, rice and millet are substitutes but the relationship is not statistically significant. Furthermore, in Senegal and Mali the relationship between rice and maize is positive but not statistically significant in the short-run. However, while the latter relationship continues to be insignificant in the Senegal in the long-run, in Mali, rice and maize have a statistically significant relationship of substitution in the long-run. The dynamic specification (long-run and short-run) for Senegal provides evidence of substitution of maize for sorghum and complementarity between maize and millet. The results also reveal that in spite of the negative association between urbanization and coarse grains (millet and sorghum) shares as shown by the correlation 144 coefficients, the expenditure elasticities are more elastic for millet and sorghum than they are for rice in Senegal and Mali. This finding is contrary to the expectation that traditional coarse grains are expenditure inelastic and warrants more investigation of starchy staples consumption behavior by place of residence within the same income group. Overall for Benin, we observe that most compensated cross-price relationships are not statistically significant in both the short-run and long-run. A possible explanation for the bizarre results for rice in Benin is the large unrecorded trade in rice between Benin and Nigeria, which has banned polished rice imports. This unrecorded trade may make the FBS per capita rice availability figures for Benin unreliable indicators of the true consumption levels. A limitation of the aggregate results is that they do not sufficiently capture the effects of structural change on consumption coming from changes in non-price factors, such as income distribution. Such estimations implicitly assume that many other factors remain constant. Even more, in most cases the national averages hide contrasting sub-national realities. The distribution of income at the sub-national or micro level is probably a more critical determinant of starchy staples consumption than is the level of aggregate national per capita expenditures. Another big limitation is the intra-annual aggregation that takes place when one uses annual data—e.g., annual price data. Delgado and Reardon (1991) argue that although aggregate results are still very useful for looking at long-term consumption trends, the diagnosis of what is really pushing consumption behavior requires micro-level work that takes into account the relevant non-price factors. Chapter 4 examines the micro-level factors that influence cereals consumption in Mali using Mali’s 2006 household budget survey data. This allows us to explore further the discrepancies found in different regions of Mali and across households of different social and economic characteristics. 145 APPENDIX 146 Table A3-1. Unit Root Tests (H0: Unit Roots) – Senegal ADF test Variable lnprice lnpmaize lnpmillet lnpsorghum Ln(P) Rice Share Maize Share Millet Share Sorghum Share PP test T-Stat. p-value lags T-Stat.(rh0) T-Stat. (t) Real Prices with trend -1.922 0.643 1 -11.083 -2.551 -2.004 0.599 1 -12.733 -2.858 -1.735 0.735 1 -8.414 -2.082 -3.93 0.011 1 -20.834 -4.545 -1.964 0.621 1 -11.167 -2.593 -2.532 0.312 1 -13.187 -2.902 -1.562 0.807 1 -5.789 -1.826 -3.432 0.047 1 -18.012 -3.932 -1.856 0.677 1 -15.608 -3.51 Differenced Real Prices With Trend -3.105 0.105 1 -24.082 -4.965 -2.780 0.204 1 -25.312 -5.788 -2.374 0.394 1 -21.639 -4.57 -4.868 0.000 1 -25.003 -6.668 -3.298 0.067 1 -24.836 -5.176 -4.447 0.002 1 -22.159 -4.915 -2.600 0.280 1 -21.442 -4.609 -5.292 0.000 1 -22.717 -5.473 -3.713 0.022 1 -26.801 -7.398 1% 5% -4.380 -3.600 -22.500 -17.900 -4.380 -3.600 p-value 0.303 0.176 0.556 0.001 0.283 0.162 0.692 0.011 0.038 D.lnprice 0.000 D.lnpmaize 0.000 D.lnpmillet 0.001 D.lnpsorghum 0.000 D.ln(X) 0.000 D.Rice Share 0.000 D.Maize Share 0.001 D.Millet Share 0.000 D.Sorghum Share 0.000 Critical values 10% ADF test -3.240 PP test (rho) -15.600 PP test (t) -3.240 Source: Author. Note: D. denotes the first-difference of variable. Asterisk (*) means we reject unit roots at 10%. 147 Table A3-2: Unit root tests (H0: Non-Stationarity/unit roots) - Senegal ADF test Variable lnprice lnpmaize lnpmillet lnpsorghum Ln(X) Rice Share Maize Share Millet Share Sorghum Share PP test T-Stat. p-value lags T-Stat.(rh0) Real Prices Without Trend -2.02 0.278 1 -11.074 -1.83 0.366 1 -9.961 -1.694 0.434 1 -6.686 -3.296 0.015 1 -19.798 -2.322 0.165 1 -10.534 -1.756 0.403 1 -5.409 -0.592 0.873 1 -1.841 -0.802 0.819 1 -1.813 -1.84 0.361 1 -14.726 Real Normalized Prices Without Trend -3.209 0.020 1 -23.768 -2.901 0.045 1 -25.288 -2.471 0.123 1 -21.413 -4.988 0.000 1 -24.889 -3.396 0.011 1 -23.064 -4.561 0.000 1 -22.126 -2.483 0.120 1 -20.966 -5.353 0.000 1 -22.718 -3.828 0.003 1 -26.845 1% 5% -3.750 -3.000 -17.200 -12.500 -3.750 -3.000 D.lnprice D.lnpmaize D.lnpmillet D.lnpsorghum D.ln(X) D.Rice Share D.Maize Share D.Millet Share D.Sorghum Share Critical values ADF test PP test (rho) PP test (t) Source: Author. Note: Asterisk (*) means we reject unit roots at 10%. 148 T-Stat. (t) p-value -2.627 -2.498 -1.910 -4.248 -2.738 -2.007 -0.697 -0.836 -3.543 0.088 0.116 0.327 0.001 0.068 0.283 0.847 0.808 0.007 -5.140 -5.969 -4.680 -6.779 -5.121 -5.049 -4.590 -5.693 -7.630 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 10% -2.630 -10.200 -2.630 Table A3-3. KPSS Test for Unit Roots-Levels (H0: Stationarity) – Senegal Variable lnprice lnpmaize lnpmillet lnpsorghum Ln(X) Rice Share Maize Share Millet Share Sorghum Share Critical Values With Trend Lag Order Test Statistics 1 0.107 1 0.097 1 0.107 1 0.058 1 0.118 1 0.147 1 0.211 1 0.073 1 0.118 10%= 0.119 2.5%=0.176 5%= 0.146 1%=0.216 Without Trend Test Statistics 0.104 0.374 0.354 0.213 0.280 0.819 0.641 0.999 0.205 10%=0.347 2.5%=0.574 5%=0.463 1%=0.739 Source: Author. Note: Asterisk (*) means we do not reject stationarity at 5%. Table A3-4. KPSS Test for Unit Roots- First Differenced (H0: Stationarity) – Senegal Variable D.lnRice D.lnMaize D.lnMillet D.lnSorghum D.ln(X) D.Rice Share D.Maize Share D.Millet Share D.Sorghum Share Critical Values With Trend Lag Order Test Statistics 1 0.070 1 0.065 1 0.086 1 0.041 1 0.057 1 0.042 1 0.070 1 0.051 1 0.092 10%= 0.119 2.5%=0.176 5%= 0.146 1%=0.216 Without Trend Test Statistics 0.070 0.065 0.087 0.047 0.107 0.085 0.195 0.057 0.097 10%=0.347 2.5%=0.574 5%=0.463 1%=0.739 Source: Author. Note; Asterisk (*) means we do not reject stationarity at 5%. 149 Table A3-5: Unit Root Tests (Non-Stationarity as the Null Hypothesis) – Benin ADF test Variable lnprice lnpmaize lnpyams lnpcassava Ln(X) Rice Share Maize Share Yams Share Cassava Share PP test T-Stat. p-value lags T-Stat.(rh0) T-Stat. (t) Real Prices with trend -1.621 0.7842 1 -8.251 -1.604 -2.274 0.4486 2 -11.233 -2.737 -2.558 0.2998 2 -18.007 -5.316 -2.902 0.1616 1 -7.211 -2.496 -3.209 0.0827 1 -6.911 -2.517 -2.594 0.2827 1 -10.423 -2.542 -2.961 0.1432 1 -11.859 -3.031 -2.027 0.5864 1 -7.357 -2.116 -2.388 0.386 1 -8.226 -2.443 Differenced Real prices with Trend -3.173 0.090 1 -19.691 -4.278 -5.803 0.000 1 -19.465 -4.356 -5.554 0.000 1 -25.576 -7.524 -4.062 0.007 2 -16.948 -4.035 -3.625 0.028 2 -15.183 -3.339 -2.532 0.312 2 -18.014 -3.946 -4.874 0.000 1 -22.409 -5.400 -2.938 0.150 2 -19.530 -4.793 -3.904 0.012 1 -22.145 -5.057 1% 5% -4.380 -3.600 -22.500 -17.900 -4.380 -3.600 p-value 0.7908 0.2211 0.0001 0.3301 0.3195 0.3072 0.1237 0.5371 0.3568 D.lnprice 0.003 D.lnpmaize 0.003 D.lnpyams 0.000 D.lnpcassava 0.008 D.ln(X) 0.060 D.Rice Share 0.011 D.Maize Share 0.000 D.Yams Share 0.001 D.Cassava Share 0.000 Critical values 10% ADF test -3.240 PP test (rho) -15.600 PP test (t) -3.240 Source: Author. Note: The asterisk (*) implies we reject non-stationarity at 10% significance level. 150 Table A3-6. Unit root tests (Non-Stationarity as the Null Hypothesis) – Benin ADF test PP test T-Stat. lnprice lnpmaize lnpyams lnpcassava Ln(X) Rice Share Maize Share Yams Share Cassava Share p-value lags T-Stat.(rh0) Real Prices Without Trend -2.124 0.2349 1 -9.846 -2.254 0.1873 2 -11.916 -0.487 0.8945 2 -11.352 -2.309 0.169 1 -7.606 -2.236 0.1934 1 -6.648 -2.68 0.0775 1 -10.255 -2.344 0.1582 1 -11.341 -2.400 0.1418 1 -7.997 -2.594 0.0942 1 -9.092 Differenced Real Prices Without Trend -3.047 0.031 1 -18.270 -5.676 0.000 1 -18.978 -5.720 0.000 1 -25.039 -3.635 0.005 2 -15.316 -3.448 0.009 2 -12.557 -2.924 0.043 2 -17.920 -4.574 0.000 1 -21.878 -3.351 0.013 2 -19.026 -3.312 0.014 1 -20.884 1% 5% -3.750 -3.000 -17.200 -12.500 -3.750 -3.000 T-Stat. (t) p-value -2.013 -2.844 -2.577 -2.233 -1.934 -2.627 -2.748 -2.469 -2.706 0.281 0.052 0.098 0.194 0.316 0.088 0.066 0.123 0.073 D.lnprice -4.042 0.001 D.lnpmaize -4.325 0.000 D.lnpyams -7.572 0.000 D.lnpcassava -3.746 0.004 D.ln(X) -3.115 0.026 D.Rice Share -4.108 0.001 D.Maize Share -5.331 0.000 D.Yams Share -4.532 0.000 D.Cassava Share -4.794 0.000 Critical values 10% ADF test -2.630 PP test (rho) -10.200 PP test (t) -2.630 Source: Author. Note: The asterisk (*) implies we reject non-stationarity at 10% significance level. 151 Table A3-7. KPSS Test for Unit Roots-Levels (Ho: Stationarity) – Benin Variable lnprice lnpmaize lnpyams lnpcassava Ln(X) Rice Share Maize Share Yams Share Cassava Share Critical Values With Trend Lag Order Test Statistics 1 0.0974 2 0.0998 2 0.1030 1 0.1960 1 0.1810 1 0.074 1 0.1820 1 0.1910 1 0.1990 10%= 0.119 2.5%=0.176 5%= 0.146 1%=0.216 Without Trend Test Statistics 0.115 0.109 0.5400 0.231 0.279 0.129 0.271 0.281 0.220 10%=0.347 2.5%=0.574 5%=0.463 1%=0.739 Source: Author. Note: The asterisk (*) implies we do not reject Stationarity at 5% significance level. Table A3-8. KPSS Test for Unit Roots- First Differenced (Ho: Stationarity) – Benin Variable D.lnRice D.lnMaize D.lnpyams D.lnpcassava D.ln(X) D.Rice Share D.Maize Share D.Yams Share D.Cassava Share Critical Values With Trend Lag Order Test Statistics 1 0.0965 1 0.0384 1 0.0695 2 0.0767 2 0.0729 2 0.0803 1 0.0475 2 0.0634 1 0.0502 10%= 0.119 2.5%=0.176 5%= 0.146 1%=0.216 Without Trend Test Statistics 0.211 0.093 0.133 0.282 0.288 0.086 0.122 0.211 0.200 10%=0.347 2.5%=0.574 5%=0.463 1%=0.739 Source: Author. Note: The asterisk (*) implies we do not reject Stationarity at 5% significance level. 152 Table A3-9. Unit Root Tests (H0: Non-Stationarity/Unit Roots) – Mali ADF test Variable lnprice lnpmaize lnpmillet lnpsorghum Ln(X) Rice Share Maize Share Millet Share Sorghum Share PP test T-Stat. p-value lags T-Stat.(rh0) T-Stat. (t) Real Prices with trend -1.463 0.841 2 -4.694 -1.387 -4.699 0.001 1 -19.183 -3.981 -4.215 0.004 1 -17.819 -3.816 -4.354 0.003 1 -19.209 -4.123 -4.284 0.003 1 -16.356 -3.561 -3.283 0.069 1 -13.888 -3.081 -3.185 0.088 1 -15.747 -3.521 -4.401 0.002 1 -13.011 -3.659 -1.892 0.659 1 -15.721 -3.257 Differenced Real Prices With Trend -5.168 0.000 1 -20.632 -4.72 -4.886 0.000 1 -23.254 -5.902 -4.333 0.003 1 -24.272 -6.081 -4.505 0.002 1 -24.91 -6.41 -4.367 0.003 1 -24.044 -5.906 -3.625 0.028 1 -24.177 -5.53 -3.540 0.035 1 -22.969 -5.378 -3.630 0.027 1 -23.479 -5.366 -3.939 0.011 1 -24.86 -6.721 1% 5% -4.380 -3.600 -22.500 -17.900 -4.380 -3.600 D.lnprice D.lnpmaize D.lnpmillet D.lnpsorghum D.ln(X) D.Rice Share D.Maize Share D.Millet Share D.Sorghum Share Critical values ADF test PP test (rho) PP test (t) Source: Author. Note: Asterisk (*) means we reject the unit roots at 10%. 153 p-value 0.865 0.009 0.016 0.006 0.033 0.111 0.037 0.025 0.074 0.001 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 10% -3.240 -15.600 -3.240 Table A3-10: Unit root tests (H0: Non-Stationarity/unit roots) - Mali ADF test Variable lnprice lnpmaize lnpmillet lnpsorghum Ln(X) Rice Share Maize Share Millet Share Sorghum Share PP test T-Stat. p-value lags T-Stat.(rh0) Real Prices Without Trend -3.187 0.021 2 -6.424 -4.742 0.000 1 -19.363 -4.001 0.001 1 -18.071 -4.407 0.000 1 -19.352 -3.797 0.003 1 -16.843 -3.178 0.021 1 -8.790 -1.622 0.472 1 -6.382 -3.758 0.003 1 -13.509 -1.208 0.670 1 -1.998 Differenced Real Prices Without Trend -3.708 0.004 1 -17.999 -4.955 0.000 1 -23.285 -4.422 0.000 1 -24.313 -4.608 0.000 1 -24.907 -4.344 0.000 1 -23.835 -3.751 0.004 1 -23.852 -3.675 0.005 1 -22.971 -3.911 0.002 1 -22.965 -3.935 0.002 1 -25.115 1% 5% -3.750 -3.000 -17.200 -12.500 -3.750 -3.000 D.lnprice D.lnpmaize D.lnpmillet D.lnpsorghum D.ln(X) D.Rice Share D.Maize Share D.Millet Share D.Sorghum Share Critical values ADF test PP test (rho) PP test (t) Source: Author. Asterisk (*) means we reject unit roost at 10%. 154 T-Stat. (t) p-value -2.968 -4.115 -3.921 -4.275 -3.595 -2.619 -2.068 -3.662 -1.020 0.038 0.001 0.002 0.001 0.006 0.089 0.258 0.005 0.746 -3.949 -5.885 -6.104 -6.428 -5.760 -5.485 -5.558 -5.423 -6.821 10% -2.630 -10.200 -2.630 0.002 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 Table A3-11. KPSS Test for Unit Roots-Levels (H0: Stationarity) – Mali Variable lnprice lnpmaize lnpmillet lnpsorghum Ln(X) Rice Share Maize Share Millet Share Sorghum Share Critical Values With Trend Lag Order Test Statistics 2 0.157 1 0.051 1 0.067 1 0.055 1 0.083 1 0.114 1 0.092 1 0.106 1 0.145 10%= 0.119 2.5%=0.176 5%= 0.146 1%=0.216 Without Trend Test Statistics 0.458 0.060 0.083 0.056 0.127 0.572 0.818 0.104 0.961 10%=0.347 2.5%=0.574 5%=0.463 1%=0.739 Source: Author. Note: Asterisk (*) means we do not reject stationarity at 5%. Table A3-12. KPSS Test for Unit Roots- First Differenced (H0: Stationarity)-Mali Variable D.lnRice D.lnMaize D.lnMillet D.lnSorghum D.ln(X) D.Rice Share D.Maize Share D.Millet Share D.Sorghum Share Critical Values With Trend Lag Order Test Statistics 1 0.056 1 0.041 1 0.043 1 0.044 1 0.043 1 0.044 1 0.060 1 0.083 1 0.079 10%= 0.119 2.5%=0.176 5%= 0.146 1%=0.216 Source: Author. Note: Asterisk (*) means we do not reject at 5%. 155 Without Trend Test Statistics 0.356 0.054 0.059 0.059 0.091 0.085 0.069 0.131 0.083 10%=0.347 2.5%=0.574 5%=0.463 1%=0.739 CHAPTER 4. HOUSEHOLD-LEVEL EVIDENCE OF CEREALS DEMAND IN URBAN AND RURAL MALI 4.1. Background and Problem Statement The aggregate, country-level analysis of food demand based on FBS data from Chapter 3 is a good starting point for understanding major drivers of the demand for starchy staples in West Africa. However, the information it provides permits only the identification of the general priorities for consumption analysis and overall food policy attention. The limitations of the FBS are quite well known: a) its failure to disaggregate supply by income class and b) its failure to provide information on the distribution of food availability geographically within a country. As a result, an analysis thereof ignores the effects of the distribution of income and of differences in food supply across regions on food demand. Such a disaggregation is essential in bringing the food situation into clearer focus. Even more, several factors at the household-level work to determine food demand behavior, and these need to be understood in order to design effective food policies. This chapter aims to provide micro-level evidence on food demand in Mali by means of a household-level disaggregated, multivariate analysis using household budget survey (HBS) data. An analysis of food demand disaggregated at the household level helps to identify households that are most vulnerable to inadequate food intake and their geographic location; and in particular in understanding the behavioral parameters underlying any adjustment to the economic environment. A multivariate analysis that is grounded in economic theory provides estimates of microeconomic measures of households’ consumption responsiveness to changes in the amount of resources available for consumption and also allows us to test the responsiveness of demand to other arguments included in the demand function (e.g., prices). Estimation at the household 156 level allows not only the incorporation of household consumption variables (economic and socio-demographic) into the analysis, but even more important, the interest of this type of analysis lies in the estimation of price and income elasticities of demand which: a) take into account differences in the distribution of income across households and b) capture the extent to which price differences resulting from differences in food supply conditions as well as differences in tastes and preferences across regions influence food demand. Such information is needed for a much precise description of food security problems, in designing programs that target food assistance efficiently and in evaluating the effect of various policies and other targeted programs to alleviate food insecurity. 4.2. Research Questions and Hypotheses The main objective of this chapter is to analyze HBS data for Mali in order to estimate consumption parameters. Separate food demand estimates will be provided by place of residence (urban/rural) and by per capita income groups. Specifically, the analysis asks the following questions:  What factors influence the demand for individual cereals and the substitution among individual cereal types?  How does food consumption behavior differ across households of different income levels?  How does the structure of food demand differ by place of residence (rural/urban)? The following hypotheses will be tested: Hypothesis 4.1: Cereals expenditure elasticities are higher for poorer than for richer households. Engel’s law also predicts that the proportion of income spent on food declines with income. We therefore expect expenditure elasticities to be higher for lower income groups. 157 Hypothesis 4.2: Rice demand is less responsive (inelastic) to price changes (relative to coarse grains) in urban areas than in rural areas. Due to the high opportunity cost of time and convenience in the urban area, one would expect urban households to prefer rice to coarse grains and therefore be less sensitive to changes in rice prices. Hypothesis 4.3: The Marshallian own-price elasticities of cereals demand are more elastic (larger in absolute terms) for lower income households than higher income households. For poorer households spending a higher percentage of their income on food (Engel’s law) the income effect of a change in the price of food is expected to be substantial and demand would be elastic. Meanwhile for richer households for which food represents only a negligible portion of the budget, the income effect will be insignificant and demand inelastic. Hypothesis 4.4: The substitution effects (cross-price elasticities) of demand across different types of cereals are higher for urban than for rural households. Rural households are often also food producing households, and they usually have available to them that which they can produce – predominantly millet and sorghum (since it is too dry in many areas to produce rice and maize). Urban households on the other hand, especially those in larger cities, quite often have a full panoply of goods available in urban markets. As a result, the substitution effects are expected to be larger in the urban areas (with a wider range of products to draw from) than in the rural areas. Hypothesis 4.5: The compensated cross-price elasticities of cereal demand will be higher for the low-income groups than for higher-income groups. For the same reason that staple food is an important share of the consumption base amongst the low-income population, low-income households are more likely to substitute across staples in the event of an increase in the price of a commodity. 158 The findings of this chapter make an important empirical contribution by reporting for the first time a set of estimates of food demand elasticities for urban and rural Malian households, by income groups and taking into account differences in households’ sociodemographic characteristics. The remainder of this chapter is organized as follows: the conceptual framework underlying the analysis; a review of relevant literature on the determinants of household demand; the data and computation of variables used in the analysis; the methodological framework, including discussion of the theoretical background for the QUAIDS demand model and of the empirical problems encountered in the specification of the model (the problem of zero expenditure on certain commodities and the problem of expenditure endogeneity); and findings. 4.3. Conceptual Framework and Literature Review 4.3.1. Household-Level Determinants of Food Demand Microeconomic analysis recognizes the role of key variables in determining demand. These variables are commonly referred to as demand “shifters”, since changes in these variables lead to changes in demand. Common household-level demand shifters include income, taste and preferences and relative prices. Other factors such as household demographic characteristics (size, age and sex composition), place of residence and geographic location also influence household demand. 4.3.1 Income Engel’s law predicts that the proportion of income spent on food declines with income, even if actual expenditure on food rises. It is widely, if not universally, acknowledged that income 159 elasticities for food items decline with income (Alderman, 1986). Inferior foods, those that decrease in demand when consumer income rises, have a potential for self-targeting.32 This makes them attractive as candidates for social safety-net programs that seek to alleviate hunger amongst the poor in a period of crisis. Households of different income groups respond differently to changes in the conditions that determine demand. As a result, designing effective food policy requires demand parameters differentiated by income groups. 4.3.1.2. Prices Consumers react to price changes by changing quantity or quality consumed. For primary products (with little quality differentiation) like cereals, it is common to find consumers making quantity adjustments and /or moving to closely related products. In theory, the total effect of a good’s price change is summarized using the Slutsky decomposition–the income and the substitution effects. The income effect is the effect on demand due to a change in consumer’s real purchasing power. The substitution effect represents the change in demand due to a relative price change. The Slutsky decomposition shows that the magnitude and the sign of the Marshallian (income constant) price elasticity depend on: a) the compensated or Hicksian (utility constant) elasticity, b) the share of the good in consumption, and c) the income elasticity of the good. Both b) and c) are usually larger for lower-income households than higher income households because of Engel’s law and also because food staples constitute a major share in the food budget for lower income groups, who are more concerned about calories quantity than quality than are higher income groups. The balance of the movements of the substitution effect and the income effect is what makes a good normal or inferior. 32 A mechanism whereby those who are in need of benefit identify themselves for or gain from the assistance. 160 For agricultural households, the effect of food price changes goes beyond the “income effect” and the “substitution effect” discussed above. Under the perspective of an agricultural household model, consumption behavior is complicated by production decisions. While most urban households are solely food consumers, most rural households are also food producers, such that changes in food prices affect them as consumers (expenditure side) and producers (income side). An increase in the price of a food commodity could increase the demand for that commodity (contrary to the traditional demand theory) since a farmer may produce more of it and gain more income. The net effect of a price change depends on the net position of the household in the food market (net-seller or net buyer). Thus, at the household level, while net food-selling households would see an increase in income that may compensate for the rise in the price of foods they purchase (the “profit effect” described by Singh et al., 1986), the net food-buying households are likely to be adversely affected by increases in the prices of foods they purchase (unless the higher agricultural prices lead to an increase in the demand for agricultural labor, which could lead to the net buyer households earning more money as agricultural laborers). A primary motive for estimating demand elasticities is to use them in estimating the welfare effects of food price changes. According to de Janvry and Sadoulet (2008), imputing changes in relative food prices to the household’s production and consumption of food crops for the computation of welfare effects of food price changes requires a household survey that gives detailed information on the consumption structure and on the production structure. Estimating the additional effect of a change in price for agricultural households on consumption requires: 1) capturing the change in income from a price change (profit effect) and 2) the corresponding change in total expenditures on a the set of commodities of interest (in this case cereals) as a result of the change in income. The estimation of the additional profit effect 161 from food price changes requires information on the production technology (input and output quantities) as well cost information (input and output costs). The ELIM 2006 HBS used in this chapter does not include information on quantities or cost of inputs used or quantities of output produced for the commodities of interest in this study. Total revenue from cereals sales is reported. However, this is not disaggregated by individual cereals type. Information on the cost of production of cereals is not available. This data limitation therefore makes it impossible to model the joint production and consumption behavior of food producing and consuming households in this chapter. 4.3.1.2.1. Estimating Price Effects in Cross-Sectional Household Survey Data Mali’s cross-sectional HBS data known as the “Enquête Légère Intégrée auprès des Ménages (ELIM)-2006” is used in this chapter. All nine regions of Mali, including the district of Bamako, were covered in the survey (Koulikoro, Segou, Sikasso, Gao, Kayes, Kidal, Mopti, Tombouctou, and Bamako). Like most HBS data, no information is provided on the prices paid by individual households for most goods. The Observatoire du Marche Agricole (OMA) is the office responsible for collecting agricultural price data. Table A4-1 in Appendix presents the structure of the ELIM-2006 data. The regions surveyed are comprised of “cercles” or districts (total=48), each of which is further divided into “arrondissements” or sub-districts. The last column in Table A4-1 shows the representative markets from which the OMA collects cereal price data. At the level of the sub-districts, there is a paucity of OMA data collection sites, limiting the degree of price variation one can get at this level. Variation in prices can therefore be obtained only at the district level. For 33 of the 48 districts, OMA monitors at least one market within the district. District-level prices can be calculated by averaging the prices from all the markets for which 162 prices are collected within each district. For the other 15 districts with no representative markets, regional-level average prices by product will be imputed. An important question that often emerges in the analyses of household food demand behavior using cross-sectional survey data (where households indicate the actual price paid for a commodity), is whether price variation can be obtained from the surveys in order to estimate a complete system of demand and price elasticities (Koç and Alpay, 2002). As stated earlier, this study makes use of cross-sectional price data from an external source. The appropriateness of cross-sectional price variations in the estimation of reliable price elasticities of demand has been widely discussed in the literature. Cross-sectional variations in prices could be due to various reasons such as region, price discrimination, seasonality and quality effects (Prais and Houthakker, 1955). Imputing prices from an external source makes it impossible to capture price discrimination and quality effects. However, when dealing with primary commodities, one expects relatively little quality variation. Price variations from regional and seasonal differences allow accurate estimation of price elasticities, and thus are desirable for demand analysis (Deaton, 1988; Cox and Wohlgenant, 1988). Friedman (1976) suggests that constructing a demand curve from spatial data is essentially similar to that from time-series data when conditions of supply vary considerably while conditions of demand vary little, which is possible for products (such as food) that have distinctive local markets with different supply conditions. Generally, price variations across regions at a given point in time are often attributed to differences in supply conditions and differences in tastes and preferences. This makes it difficult to infer causality to regionally different consumption patterns even when prices are different. Deaton (1997) notes that it is often desirable to allow for the effects of regional and seasonal 163 taste variation in the pattern of demand by entering regional and seasonal dummies into the regression, so that the price effects on demand are only identified to the degree that there are multiple observations within regions or that regional prices do not move in parallel across seasons. Dummy variables will be introduced to isolate changes in demand from differences in taste and preference from changes in demand from changes in prices. Deaton (1988) shows that under appropriate separability conditions, one can exploit the spatial nature of data to back out true price elasticities. The idea is that within a geographic unit (say district) the prices will be the same, and controlling for district-level fixed effects allows one to back out the true price elasticities because the real price variation occurs only through the spatial dimension. Thus, even though the survey is a one shot survey, multiple observations of prices (district-level) within a region allow us to capture some temporal variability in prices, which when combined with regional dummy variables permits us to obtain estimates of price elasticities by income group. 4.3.1.3. Taste and Preferences Food demand is also strongly influenced by changes in tastes and preferences. Taste and preferences may change over time (e.g., due to globalization), across regions and with ethnicity. In a cross-sectional setting, one can capture variations in taste and preferences across regions but not across time. The use of regional dummy variables enables us to isolate the effect on demand from differences in taste and preferences (across regions) from other effects. 164 4.3.1.4. Household Socio-demographic Characteristics Socio-demographic characteristics, such as family size and composition (sex and age), inf1uence household expenditure patterns and hence are important variables in policy design and analysis. Teklu (1996) observes that an increase in household size leads to a less than proportional increase in food consumption. That is, the elasticity of demand for food with respect to size is less than unity—holding per capita income constant (there are economies of scale in consumption). Savadogo and Brandt (1988) in urban Burkina Faso showed that such economies of scale in consumption are larger for high-income groups, who had higher levels of food consumption, such that the effect of an increase in household size on food consumption is lower at the margin. Moreover, an increase in household size induces a reallocation of food budget away from food groups that are income-elastic towards income-inelastic food staples (Savadogo and Brandt; 1988). Demand patterns may also vary across age (child and adult goods) and sex within the households. 4.3.1.5. Geographic Location Geographic regions differ in climatic and infrastructure conditions and hence in the availability of food and consumption habits (composition of the food basket). Wodon and Zaman (2010) observe that the distributional impact of rising food prices affects poor households partly based on where they live, which poses a challenge for policymakers. In the development and targeting of food safety net interventions to help households cope with the increase in food prices, policymakers therefore need to identify the hardest hit areas which: a) may not necessarily be among the poorest in the country; and b) are also not always homogenous in terms of income or 165 other indicators of household vulnerability. Regional dummies are used to isolate geographic differences in consumption and not just those due to taste and preferences discussed above. 4.3.1.6. Place of Residence Rural and urban consumption patterns are different due to differences in economic activity and lifestyle. Rural livelihoods are mostly dependent on agriculture, and rural areas account for much of the food consumed in Mali. Kelly et al. (2008) note that even in the import-dependent Sahelian countries, production of coarse grains persists in the rural areas such that while the urban consumers heavily rely on imported cereal for food, rural households also heavily rely on traditional coarse grains for their dietary needs and have a lower level of rice consumption. Not only do rural and urban consumers have different base levels of food consumption (at the commodity level), but also, time is an important factor that brings about differences in rural and urban consumption habits. Kennedy and Reardon (1994) found that in urban Burkina Faso the opportunity cost of women’s time was a major factor in the choice of coarse grains versus-nontraditional grains. Women who worked outside the home were found to have a strong preference for rice, which took less time to cook than coarse grains. Earlier studies of food consumption patterns in the Sahel have focused largely on urban households, based on the notion that they rely on the market for most of their consumption because of their lifestyle. Changes in relative prices of food were therefore expected to hurt these urban consumers more than rural dwellers. According to Kelly et al. (2008), a challenge in the current food crisis situation is the difficulty to assess the relative vulnerability of urban versus rural groups. They explained further that because the price hikes to date are greatest on imported cereals consumed more by urban than rural populations, there is a tendency to think of this more 166 as an urban problem. However, to the extent that these higher prices are transmitted to domestic cereals and rural markets, or supplies of domestic cereals become tight, the vulnerability may be as great in rural areas. Thus, a comprehensive understanding of food consumption patterns requires giving consideration to both rural and urban households. 4.4. Data and Computation of Relevant Variables The ELIM-2006 HBS data covered 4494 Malian households, urban (1594) and rural (2910), and 9 regions including the district of Bamako. Data were collected on household economic and socio-demographic characteristics and expenditures by major categories (food and non-food). Food expenditures are further divided into major food groups (cereals and non-cereals foods) and cereals expenditures are grouped by cereal crop type. Total consumption expenditures per expenditure category sums the value of consumption on a given category from all sources (includes purchases, own-production and from other modes of acquisition). Household adult equivalents (AE) are calculated by aggregating the determined AE of the respective household members. The AE for each household member is calculated using the scale: male>14 years=1.0; female>14=0.8; children=0.5 (Duncan, 1994). Total expenditure on all household expenditure categories is used as a proxy for household income. Expenditure shares are calculated as the proportion of each expenditure group in total expenditure for the aggregate group considered. 4.5. Methodological Framework 4.5.1. Commodity Aggregation and Weak Separability The analysis assumes that consumers’ preferences are weakly separable in order to simplify the modeling of consumption decisions. Without the assumption of weak separability, the 167 optimization problem is intractable for the consumer if the demand for every commodity is a function of the prices of all other commodities (Deaton and Muelbauer, 1980). Under this assumption, the consumer’s simultaneous decision-making process can be broken down into a three-stage budgeting process. In Stage I, households allocate total budget between food and non-food items. Conditional on the first stage allocations, in Stage II, households allocate food expenditure between cereals and non-cereals items. In Stage III, conditional on the second stage allocations, households allocate cereal expenditures to rice, maize, millet and sorghum. It is thus assumed that food is weakly separable from non-food commodities and that cereals are weakly separable from other food groups. The focus of this chapter is Stage III, the reason being that not only is it more interesting and useful, but also the lack of price/cost information for most nonfood items and non-cereals food items makes the estimation of Stages I and II less feasible. 4.5.2. Modeling Approach The allocation of total cereals expenditures to specific cereals types (Stage III) is modeled using the quadratic almost ideal demand system (QUAIDS) proposed by Banks et al. (1997). Unlike its predecessor, the AIDS of Deaton and Muelbauer (1980), which has budget shares that are linear functions of log total expenditure and are derived from indirect utility functions that are themselves linear in log total expenditure (Muelbauer, 1976), the QUAIDS model allows for non-linearity in the budget shares. As a complete demand system, the QUAIDS allows us to consistently account for the interdependence in the choices made by households between different cereal types. By nesting the AIDS model, the QUAIDS model maintains all the relevant properties of the former (allows for exact aggregation over households and satisfies all the axioms of choice). In addition to these advantages, the QUAIDS specification allows for more 168 flexibility—expenditure elasticities differ with expenditure levels. This could be a significant advantage in welfare analysis. It also allows the possibility of normal goods becoming inferior or vice versa as one move along the expenditure spectrum of households (Bopape, 2006). 4.5.2.1. Model Specification Test The choice between estimating an AIDS or a QUAIDS model rests on the shape of the Engel curves. Bopape (2006) developed a parametric quadratic expenditure specification test for whether the QUAIDS or the AIDS is appropriate for the demand analysis. The test is based on the fact that the QUAIDS model is rank 3, exactly aggregable and has a coefficient on the linear expenditure term that is independent of the prices. It involves testing for the statistical significance of prices in the coefficient on the quadratic expenditure term in the QUAIDS model. The null hypothesis of the test is that the coefficient on the quadratic expenditure term is independent of prices across all the budget share equations. This test is a Lagrangian multiplier (LM) test, and it has the advantage of allowing one to test parametrically if the quadratic expenditure is necessary without having to estimate the highly non-linear QUAIDS model. This test is carried out to decide between the QUAIDS and AIDS models. 4.5.2.2. Problems in Demand System Estimation Zero-expenditure and expenditure endogeneity have been identified as common econometric issues that arise when cross-sectional data is used to estimate elasticities. These issues need to be addressed in order to obtain unbiased and efficient price elasticities (Chuang et al. 2005). 169 4.5.2.2.1. Zero-Expenditure Zero-expenditure arises when a large number of households report zero expenditure for some commodities/aggregates for which demand is being estimated. This causes a censored dependent variable problem that leads to biased results if not dealt with. This problem presents an empirical difficulty because the random disturbances have non-zero means and are correlated with the exogenous variables (Alfonzo et al. 2006). Tables A4-2 and A4-3 in Appendix show zero expenditure in the entire sample and by cereal type and by mode of acquisition, respectively. There is a large proportion of zero expenditure, ranging from 5.1% for rice to 49.8% for maize. Dropping these households would dramatically reduce the sample size (loss in large number of degree of freedom) and still give inconsistent estimates. Given that censoring is severe in the sample, we need a censored system approach. To address this problem, various estimation methods based on a two-step decision process initially proposed by Tobin (1958) have been utilized. Heien and Wessells (1990) introduced a two-step estimation procedure based on Heckman’s (1978) work. However, Shonkwiler and Yen (S and Y) (1999) demonstrated the inconsistency of Heien and Wessels’ two-step estimation procedure and they proposed an alternative approach for equation systems with limited dependent variables. This chapter uses the S and Y approach. Bopape (2006) and Alviola et al. (2010), Ecker and Quaim (2008), and Tafere et al. (2010) also use this approach for QUAIDS estimation. 170 4.2.5.2.2. Expenditure Endogeneity (EE) The problem of EE33 arises when total expenditures are determined jointly with the expenditure shares of the individual commodities that enter the demand model, making it endogenous in the expenditure share equations (Blundell and Robin, 1999). This problem may also arise whenever the household expenditure allocation process is correlated with other unobserved behavior not captured by the explanatory variables in the budget share equations, because these unobserved effects would be bundled in the error term. Estimation that ignores EE may lead to inconsistent demand parameter estimates (Bopape, 2006). This is because a key assumption of regression analysis is violated—that the mean of the disturbance term is zero and that the disturbance term is independent of the regressors so that the covariance between the disturbance term and the independent variables is zero. Bopape (2006) notes that because the problem of EE may affect the results of the LM test for model specification, it is important to address the problem before performing the test. Thus, for more reliable results, the LM test should be applied to estimated budget share equations that have been corrected for potential EE if EE is identified as a problem with the data. The augmented regression technique of Hausman (1978) and Blundell and Robin (1999) has been widely used to deal with the problem of EE. This technique is suitable in a system of non-linear equations. Barslund (2011) applies this technique to a system of censored demand Most empirical demand analyses do not cover all products that households purchase. As a result, the practice is to assume separable preferences and estimate a set of conditional demands for the goods of interest as functions of prices and total expenditure on these goods (Pollak and Wales, 1969). However, such a practice raises questions regarding the possibility of simultaneity bias in the budget share equations of the demand model. 33 171 equations based on the AIDS. Bopape (2006) and Tafera et al. (2010) also use the same technique to deal with the issue of EE in the context of a QUAIDS model. The augmented QUAIDS share equations are specified as follows: 8 𝑤𝑖ℎ = 𝛼𝑖 + 𝛿𝑖ℎ 𝑙𝑛𝐴𝐸ℎ + 𝜃𝑖 𝑀ℎ + ∑ 𝜌𝑖𝑛 𝑅𝐷ℎ + ∑ 𝑛=1 𝜆𝑖 𝐶𝑋ℎ 2 {𝑙𝑛 [ ]} + 𝑢𝑖ℎ 𝑏(𝑝ℎ ) 𝑎(𝑝ℎ ) 𝑘 𝑗=1 𝛾𝑖𝑗 𝑙𝑛𝑝𝑗ℎ + 𝛽𝑖 𝑙𝑛 [ 𝐶𝑋ℎ ]+ 𝑎(𝑝ℎ ) (4 − 1). wih is the household budget share for cereal type i. The budget shares are calculated using food expenditures. pih is the retail price of each cereal type 𝑖̇. C𝑋ℎ is household cereal expenditure. Dummy variables will capture the effect of a household’s geographic location on expenditures. RDh , are regional dummies. Mh represents a dummy for place of residence (urban=1 and rural=0) of a household. The translog price aggregator, a(𝑝ℎ ), and the price aggregator function, b(𝑝ℎ ), are functions homogeneous of degree 1 and 0, respectively, in prices. ln a(𝑝ℎ ) and lnb(𝑝ℎ ) are specified as translog and Cobb-Douglas equations34. The theoretical restrictions of homogeneity, adding up and symmetry are the same as discussed in chapter 3, in addition to: 𝐾 ∑ λ𝑖 = 0 ∀𝑖 𝑖=1 1 𝛽 ln 𝑎(𝑝ℎ ) = 𝛼0 + ∑𝑘𝑖=1 𝛼𝑖 𝑙𝑛𝑝𝑖ℎ + 2 ∑𝑘𝑖=1 ∑𝑘𝑗=1 𝛾𝑖𝑗 𝑙𝑛𝑝𝑖ℎ 𝑙𝑛𝑝𝑗ℎ 𝑎𝑛𝑑 𝑏(𝑝ℎ ) = ∏𝑘𝑖=1 𝑝𝑖ℎ𝑖 . For commodities i=1,…k. 34 172 To deal with the problem of EE, assume that the error terms have an orthogonal decomposition 𝑢𝑠𝑖 = 𝜌𝑠 𝜏𝑠𝑖 + 𝜀𝑠𝑖 (4 − 2) 𝜏𝑠𝑖 are the residuals from the regression of total cereal expenditure on the set of instruments and explanatory variables. 𝜀𝑠𝑖 is normally distributed. The parameter 𝜌𝑠 provides a test of exogeneity of total cereal expenditure for each consumption share and should be equal to zero if the cereal expenditure is exogenous. To deal with the problem of censoring, following the S and Y approach, consider the dichotomous variable 𝑑𝑖ℎ = 1 𝑖𝑓 𝜎𝑖 𝑧𝑖ℎ + 𝑣𝑖ℎ > 0 ; 𝑎𝑛𝑑 𝑑𝑖ℎ = 0 𝑜𝑡ℎ𝑒𝑟𝑤𝑖𝑠𝑒 (4 − 3) Where 𝜎𝑖 is a vector of coefficients, 𝑧𝑖ℎ a vector of explanatory variables and 𝑣𝑖ℎ is the equationspecific error term, which is distributed normally (0,1). The observed expenditure shares for the hth household are given by: 𝑜𝑏𝑠 𝑤𝑖ℎ = (𝑤𝑖ℎ + 𝜌𝑠 𝜏𝑠𝑖 ) ∙ 𝑑𝑖ℎ (4 − 4) Consistent parameters in equation 4-1 can be obtained by estimating 𝑜𝑏𝑠 𝑤𝑖ℎ = Ф(𝜎̂𝑖 𝑧𝑖ℎ )(𝑤𝑖ℎ + 𝜌𝑠 𝜏𝑠𝑖 ) + 𝜋𝑖 𝜙(𝜎̂𝑖 𝑧𝑖ℎ ) + 𝜉𝑖ℎ (4 − 5) Where σ ̂i zih are predicted indices from the first-step probit estimation of the equation in (4-3) and Ф and ϕ are respectively the standard normal cumulative distribution (cdf) and probability density (pdf) functions. Unlike in the conventional system specification without censoring, the deterministic components on the right hand side of equation (4-5) do not add up to unity across all equations of the system, and so the error terms in the estimation form do not add up to zero (Yen et al., 2002). As a result, the usual procedure of imposing the adding-up 173 restriction on the system and dropping one equation is not valid. Therefore, with censoring, equation (4-5) is estimated correctly when using the entire set of n equations (Yen et al., 2002). The expressions for the elasticities following Banks et al. (1997) are simplified as follows: 𝑜𝑏𝑠 𝜕𝑤𝑖ℎ 2𝜆𝑖 𝐶𝑋ℎ 𝜇𝑖 ≡ = Ф(𝜎̂𝑖 𝑧𝑖ℎ ) [𝛽𝑖 + {𝑙𝑛 [ ]}] 𝜕𝑙𝑛𝐶𝑋ℎ 𝑏(𝑝ℎ ) 𝑎(𝑝ℎ ) (4 − 6) 𝐾 𝑜𝑏𝑠 𝜆𝑖 𝛽𝑗 𝜕𝑤𝑖ℎ 𝐶𝑋ℎ 2 𝜇𝑖𝑖 ≡ = Ф(𝜎̂𝑖 𝑧𝑖ℎ ) ⌈𝛾𝑖𝑗 − 𝜇𝑖 (𝛼𝑖 + ∑ 𝛾𝑗𝑙 𝑙𝑛𝑝𝑙ℎ ) − {𝑙𝑛 [ ]} ⌉ 𝜕𝑙𝑛𝑝𝑖 𝑏(𝑝ℎ ) 𝑎(𝑝ℎ ) (4 − 7) 𝑙=1 Expressing the formula for expenditure elasticities in terms of 𝜇𝑖 : 𝜇𝑖 𝑒𝑖 = +1 𝑤𝑖 (4 − 8) Similarly, the Marshallian or uncompensated elasticities of demand can be expressed as follows: 𝜇𝑖𝑗 𝑢 𝑒𝑖𝑗 = − 𝛿𝑖𝑗 (4 − 9) 𝑤𝑖 Where δij is the Kronecker delta equating 1 if i=j and 0 otherwise. The Hicksian or compensated elasticities can be derived as thus using Slutsky equation ecij = euij + wi ei (4 − 10) 4.6. Estimation Method The complete estimation procedure for Stage III follows this pattern: in step one, a test for endogeneity of the total cereal expenditure is carried out using instrumental variables; in step two, a model specification test is carried out to determine the appropriateness of the AIDS versus QUAIDS model; in step 3 the system (4-3) is estimated by multivariate probit and the pdfs and cdfs are computed; in step 4 the system in 4-5 is estimated using Non-linear, Seemingly Unrelated Regression (NLSUR) in STATA. To capture differences in expenditure patterns across income groups, households will be divided into income groups and the consumption behavior for 174 each of the groups will be analyzed separately. Households will be ranked from lowest to highest based on per capita income levels and divided into three income groups (low, middle, and high), of equal sizes by place of residence. This is a common approach in system demand estimations. 4.7. Findings The presentation of findings begins with a descriptive summary of the data. Then further descriptive statistics of the data are presented for Stage III, and the estimated coefficients are presented and discussed. In addition, income and price elasticities of cereals demand are examined for Stage III. 4.7.1. General Descriptive Summary of the Data The final ELIM-2006 dataset used in this chapter comprised 4454 households; 1566 of the households reside in urban areas while 2888 of the households reside in rural areas. Table 4-1 presents the distribution of the sample by place of residence and by geographic region. Table 4-2 examines the relationship between household size and place of residence. This table reveals that urban households are on average smaller (8.2 individuals) than rural households (9.6). The average household AE is 6.2 in the urban areas and 7.0 in the rural areas. Table 4-2 also shows that about 54% of rural households and about 44% of urban households have more than 8 members. Table 4-3 shows that over 50% of the entire sample has household heads with no formal education. Table 4-4 also shows that only about 7% of the households in the sample have female heads, and the average age for household heads in the sample is about 49 years. Table 4-5 shows the distribution of household head (HHH) by socio-economic group and by region. The figures illustrate that close to 50% (Kayes and Segou) and over 50 % (Koulikoro, Sikasso, 175 Mopti, Tombouctou, and Kidal) of the household heads are independent farmers. The District of Bamako, as expected, has the smallest number of cases where household heads are independent farmers. 176 Table 4-1. Distribution of Data by Region and Place of Residence Region Urban Freq. Percent Freq. Kayes 164 10.47 422 Koulikoro 208 13.28 754 Sikasso 185 11.81 438 Ségou 263 16.79 630 Mopti 150 9.58 300 Tombouctou 94 6.00 258 Gao 78 4.98 60 Bamako 399 25.48 0 Kidal 25 1.60 26 Total 1,566 100 2,888 Source: Author’s computation using ELIM-2006 data. Rural Percent 14.61 26.11 15.17 21.81 10.39 8.93 2.08 0.00 0.90 100 All Freq. 586 962 623 893 450 352 138 399 51 4,454 Table 4-2. Relationship between Household (HH) Size Group and Place of Residence Household Size Group Urban Freq. 211 655 372 328 1,566 Rural Percent 13 42 24 21 100 1 to 3 4 to 7 8 to 10 10 plus Total Average HH size 8.2 Average HH AE 6.2 Source: Author’s computation using ELIM-2006 data. 177 Freq. 219 1,103 698 868 2,888 Percent 8 38 24 30. 100 9.6 7.0 Table 4-3. Level of Education of Household Head (HHH) Level of Education Urban None Fundamental 1 Partial Fundamental 1 Complete Fundamental 2 Partial Fundamental 2 Complete Post Fundamental Total Source: Author’s computation using ELIM-2006 data. Rural 653 124 61 145 87 496 1,566 2,534 150 52 52 25 75 2,888 Table 4-4. Distribution of Households by Sex and Age of Household Head By Sex of HH-Head Urban Rural Total Male 1390 2757 4147 Female 176 131 307 Total 1566 2888 4454 Source: Author’s computation using ELIM-2006 data. 178 By Age of Household Head National 49.4 Urban 47.7 Rural 50.4 Table 4-5. Socioeconomic Group of Household Head by Region HH-Head Socioeconomic Group Public Employee Private Employee Employer Independent Agric Independent non Agric Other Employment Unemployed Total Public Employee Private Employee Employer Independent Agric Independent non Agric Other Employment Unemployed Total Kayes Freq. % 37 6 34 6 2 0 290 49 99 17 Koulikoro Freq. % 61 6 52 5 19 2 588 61 107 11 Sikasso Freq. % 47 8 24 4 16 3 364 58 49 8 Segou Freq. 75 49 17 429 115 % 8 5 2 48 13 10 114 586 2 133 962 31 92 623 10 198 893 1 22 100 2 19 100 0 14 100 5 15 100 Mopti Freq. % 58 13 20 4 4 1 247 55 Tombouctou Freq. % 17 5 14 4 244 69 Gao Freq. % 32 23 27 20 45 33 Bamako Freq. % 87 22 62 16 12 3 22 6 58 63 450 47 30 352 19 15 138 138 1 77 399 13 14 100 13 9 100 14 11 100 Table 4-5. Con’td Socioeconomic Group of Household Head by Region HH-Head Kidal Socioeconomic Group Freq. Public Employee 58 Private Employee 20 Employer 4 Independent Agric 247 Independent non Agric 58 Other Employment Unemployed 63 Total 450 Source: Author’s computation using ELIM-2006 data. 179 % 13 4 1 55 13 14 100 35 0 19 100 Table 4-6 shows the annual average total household expenditure including the opportunity value for all own-produced items by place of residence. The average annual exchange35 rate for 2006 was used to convert the CFA franc amounts to their United States (US) dollar equivalent. The figures illustrate that total annual expenditures per household and per capita are generally higher in the urban areas than in the rural areas. Furthermore, in the urban areas, consumption expenditures are higher in Bamako than in the other urban areas. Households were ranked from lowest to highest based on their per capita consumption expenditures and by place of residence. The households in each place of residence (urban and rural) were then divided into three income groups, with households in each income group comprising about one-third of the total sample. The urban (rural) low-income group’s annual expenditures per capita are less than 220,053 (102,138) CFAF. The urban (rural) middle income group’s annual expenditures per capita are between 222,193 (102,312) and 437,701 (161,506) CFAF. The urban (rural) high-income group’s annual expenditures per capita exceeded 437,942 (161,691) CFAF. Table 4-7 and 4-8 also show average total consumption expenditures by income group and place of residence, per household and per adult equivalent (AE) respectively. The division by income group is done separately for the rural and urban subsamples. 35 The average annual exchange rates were obtained from www.Oanda.com. 180 Table 4-6. Annual Average Total Consumption Expenditures (CFAF) by Place of Residence Bamako Obs 399 Other Urban 1,167 Rural 2,888 Per Household Mean SE (Mean) 4,534,634 190,029 (8,389) (352) 2,528,883 65,047 (4,678) (120) 1,328,788 22,087 (2,458) (41) Per Capita Bamako 399 625,351 27,620 (1,157) (51) Other Urban 1,167 372,098 10,159 (689) (19) Rural 2,888 156,675 2,463 (290) (5) Per Adult Equivalent Bamako 807,749 693,461 399 (1,494) (1,283) Other Urban 488,934 441,462 1,167 (905) (817) Rural 212,894 176,604 2,888 (394) (327) Source: Author’s computation using ELIM-2006. Note: The figures in parenthesis are the US dollar equivalent. 181 Min 154,800 (286) 38,415 (71) Max 28,300,000 (52,355) 16,500,000 (30,525) 44,300 (82) 17,100,000 (31,635) 65,173 (121) 9,604 (18) 13,363 (25) 3,858,600 (7,138) 3,316,470 (6,135) 2,036,649 (3,768) 85,009 (157) 16,702 (31) 20,559 (38) 4,753,838 (8,795) 4,332,896 (8,016) 2,870,332 (5,310) Table 4-7. Annual Average Total Consumption Expenditures (CFAF) Per Household by Income Group and Place of Residence Urban Income Group Obs Mean SE. (Mean). Low 1,375,659 41,759 522 (2,545) (77) Middle 2,624,424 72,556 522 (4,855) (134) High 5,119,698 160,300 522 (9,471) (297) Rural Low 803,385 16,050 963 ( 1,486) (30) Middle 1,235,347 23,403 963 (2,285 ) (43) High 1,948,274 53,820 962 (3,604 ) (100) Source: Author’s computation using ELIM-2006. Note: The figures in parenthesis are the US dollar equivalent. Min Max 38,415 (71) 228,500 (423) 448,600 (830) 8,350,000 ( 15,448) 12,400,000 (22,940) 28,300,000 (52,355) 44,300 (82) 160,733 (297) 172,930 (320) 4,800,000 (8,880) 5,930,000 (10,971) 17,100,000 (31,635 ) Table 4-8. Annual Average Total Consumption Expenditures (CFAF) Per Adult Equivalent by Income Group and Place of Residence Urban Income Group Obs Mean SE. (Mean). Low 197,931 66,336 522 (366) (123) Middle 423,478 91,306 522 (783) (169) High 1,089,084 647,004 522 (2,015) (1,197) Rural Low 99,421 28,915 963 (184) (53) Middle 177,400 28,529 963 (328) (53) High 362,015 235,838 962 (670) (436) Source: Author’s computation using ELIM-2006. Note: The figures in parenthesis are the US dollar equivalent. 182 Min Max 16,702 (31) 228,500 (423) 464,975 (860) 350,447 (648) 727,611 (1,346) 4,753,838 (8,795) 20,559 (38) 109,706 (203) 174,485 (323) 169,585 (314) 265,319 (491) 2,870,332 (5,310) The households’ total food expenditure includes expenditures on food purchased and the value of consumption from own production. Table 4-9 shows average annual food and non-food expenditures by place of residence in CFAF. The figures reveal that food and non-food expenditures are higher for Bamako than for other urban areas and rural areas in both per household and per adult equivalent terms. Average annual food expenditure per AE for Bamako is 212,571 CFAF, compared to 166,842 CFAF for other urban areas and 113,442 CFAF for rural areas. Table 4-10 also shows the distribution of food and non-food expenditures by income group and by place of residence. We observe an increase in food and non-food expenditure per household and per household adult equivalent from the low to the high income group within the urban and rural locations. Also, urban per AE food expenditures are higher than rural per AE food expenditures across all income groups. Table 4-9. Average Annual Food and Non-Food Expenditure (CFAF) by Place of Residence Bamako (N=399) Other Urban (N=1167) Per Household Food 1,243,871 907,997 (2,301) (1,680 ) Non-food 3,290,763 1,620,887 (6,088) (2,999) Per Adult Equivalent Food 212,571 166,842 (393) (309) Non-food 595,178 322,092 (1,101) (596) Source: Author’s computation using ELIM-2006. The figures in parenthesis are the US dollar equivalent. 183 Rural (N=2888) 705,161 (1,305 ) 623,627 (1,154 ) 113,442 (210) 99,452 (184) Table 4-10. Average Annual Food and Non-Food Expenditure (CFAF) by Place of Residence and Income Group Urban Food Rural Obs Non food Obs Food Per Household Low 522 723,552 652,107 963 480,024 (1,339 ) (1,206) (888) Middle 522 1,039,077 1,585,347 963 729,176 (1,922) ( 2,933) (1,349) High 522 1,218,093 3,901,605 962 906,493 (2,253 ) (7,218) (1,677) Per Adult Equivalent Low 522 106,852 91,079 963 60,452 (198 ) (168) (112) Middle 522 173,598 249,881 963 108,214 (321) (462) (200) High 522 255,030 834,054 962 171,721 (472) (1,543) (318) Source: Author’s computation using ELIM-2006. Note: The figures in parenthesis are the US dollar equivalent. Non food 323,361 (598) 506,172 (936) 1,041,782 (1,927) 38,969 (72) 69,186 (128) 190,295 (352) The analysis of weighted36 food expenditure shares reveals that the share of food in total household consumption budget is smallest for the region of Bamako (0.30). Table 4-11 shows weighted food shares by region. Table 4-12 also shows food shares by place of residence and per capita expenditure income group. The table shows that for the entire sample, the share of food in total household consumption expenditure is 0.43. The national average conceals a discrepancy between the urban and rural food shares. Considering all urban areas, the food share is just 0.35, as opposed to a share of 0.53 in the rural areas. A breakdown of food share by income groups shows that irrespective of place of residence, there is a decline in food share as we move from 36 Using the weight of the household in the total sample. 184 the low-income group to the high-income group (Engel’s law). However, the difference in the food share between the low- and middle-income group is in both the rural and urban areas is not as large as the difference in food share between the middle- and the high-income group. Table 4-11. Weighted Food Expenditure Shares by Region Region Kayes Koulikoro Sikasso Ségou Mopti Tombouctou Gao Bamako Kidal Source: Author’s computation using ELIM-2006 Share 0.50 0.48 0.40 0.48 0.49 0.56 0.54 0.30 0.44 Table 4-12. Weighted Food Shares by Income Group and Place of Residence Income Group National Low 0.59 Middle 0.55 High 0.34 All 0.43 Urban Rural 0.53 0.60 0.41 0.59 0.26 0.35 0.47 0.53 Source: Author’s computation using ELIM-2006. A locally weighted regression (nonparametric method based on fitting a linear model to observations in a neighborhood of a point) was carried out using the “lowess” command in STATA to examine graphically (Figure 4-1) the relationship between food expenditures per capita and total household consumption expenditure per capita. The graph illustrates that 1) food 185 expenditure per capita increases with total consumption expenditures per capita; 2) the estimated slope of the relationship (the conditional mean) becomes flatter as total household consumption expenditure per capita increases; 3) the dispersion increases with income levels. Furthermore, a graphical examination of the relationship between food shares and total household consumption expenditure (Figure 4-2) shows: 1) an inverse relationship between food share and the log of total household consumption expenditure (Engel’s law is satisfied): households with a lower total expenditure level tend, on average, to spend a higher fraction of their income on food; and 2) the dispersion is higher at low levels of total household consumption expenditure. 0 100000 200000 300000 400000 Figure 4-1. Food Expenditures per Capita and Total Household Consumption Expenditures per Capita (CFAF) 0 1000000 2000000 3000000 total hh per capita consumption expenditures lowess food_pcexp totcons_pcexp Source: Author. 186 food_pcexp 4000000 0 .2 .4 .6 .8 1 Figure 4-2. Food Expenditure Shares and Total Household Consumption Expenditures 10 12 14 lnX 16 lowess foodexp_share lnX 18 foodexp_share Source: Author. Table 4-13 also reveals that mean expenditures on cereals per household and per AE are higher for the urban area than the rural area summing across all income groups. While in the rural area average expenditure on cereals increases from the low- to the high-income group, in the urban area average expenditure on cereals increases from the low- to the middle-income group, but declines from the middle- to the high-income group. A breakdown of food expenditure per adult equivalent by place of residence and income group (Table 4-13) also shows that cereals expenditures per AE (CFAF/AE) increases with income level irrespective of the place of residence. However, while the average expenditures per AE on cereals are higher for the urban low (middle) income than the rural low (middle) income 187 groups, average cereals expenditure per AE are higher for the rural high income than the urban high income. That the average expenditure on cereals per AE is higher for the rural high-income group than the urban high-income group does not imply that the rural high-income households spend more in the market on cereals than do their urban counterparts because this descriptive summary of cereals consumption includes the value of cereals from all sources (own production and purchases). Because many rural households produce some cereals for their own consumption, netting out the value of consumption from own-production could show that urban high-income households on average spend more on cereals than rural high-income households. Also, this pattern in cereals expenditure per AE by income group and place of residence also points to the fact that the value of consumption from own-production makes a difference only for the high-income group. Furthermore, given that the entire sample was first divided by place of residence, and per capita income groups were computed separately by place of residence, the high-income group in the rural area has a lower income than the high-income group in the urban area. Table 4-14 reports the weighted share of cereals in household food expenditure by region. The figures illustrate that with the exception of Bamako, which has an average cereal share below 30%, in all other regions, cereals occupy greater than 30% of the household’s food budget. Table 4-15 reports a breakdown of the cereals share by income group and place of residence. The figures illustrate that for all households combined, cereals represent about 40% of the food budget. In urban areas, however, the share is 33% while in rural areas the share is about 46%. The share of cereals in the food budget decreases from the low- to the high-income group within each place of residence. However, in both locations, the difference between the low- and middleincome groups in cereals share is quite small compared to the difference between the middle188 and the high-income groups. It is acknowledged here that cereals and non-cereals are highly aggregated groups. Cereals expenditures are further disaggregated in the next sub-section of this chapter. For a breakdown of expenditure and expenditure shares in the non-cereals food group, interested readers are urged to refer to Taondyandé and Yade 2012; and Kelly et al. 2012. Table 4-13. Average Annual Cereals and Non-Cereals Expenditure (CFAF) by Place of Residence and Income Group Urban Rural Per Household (CFAF) Income Group Cereals Non-Cereals Cereals Non-Cereals Low 286,519 437,032 221,952 258,073 (530) (809) (411) (477) Middle 368,221 670,856 341,857 387,319 (681) (1,241 ) (632) (717) High 306,188 911,905 377,647 528,845 (566) (1,687 ) (699) (978) All Groups 320,309 673,264 313,797 391,365 (593) (1,246) (581) (724) Per Adult Equivalent (CFAF/AE) Urban Rural Income Group Cereals Non-Cereals Cereals Non-Cereals Low 42,209 64,643 27,997 32,455 (78) (120) (52) (60) Middle 59,842 113,756 49,809 58,405 (101) (210) (92) (108) High 63,021 192,009 70,574 101,147 (117) (355) (131) (187) All Groups 55,024 123,469 49,453 63,989 (102) (228) (91) (118) Source: Author’s computation using ELIM-2006. The figures in parenthesis are the US dollar equivalent. 189 Table 4-14. Cereals Expenditure Shares by Region Region Share Kayes Koulikoro Sikasso Ségou Mopti Tombouctou Gao Bamako Kidal Source: Author’s computation using ELIM-2006 35 42 42 41 47 48 52 28 33 Table 4-15. Cereal Shares by Income Group and Place of Residence Income Group Low Middle High National 0.46 0.45 0.33 All 0.40 Source: Author’s computation using ELIM-2006 Urban 0.40 0.35 Rural 0.47 0.48 0.25 0.33 0.43 0.46 As seen from Figure 4-3, the share of cereals in the food budget seems to decrease as the household food budget increases. This relationship is not surprising. Cereals are major staples in Mali, and at lower income levels, households are more concerned about quantity (having a full stomach) rather than quality. It is likely that as the total food income continues to grow, households begin to think about diversifying their diets–maybe by eating higher quality and expensive foods such as meats and vegetables. The end result is that the share of cereals drops while the shares of other food groups increase. 190 0 .2 .4 .6 .8 1 Figure 4-3. Total Household Food Expenditure and the Share of Cereals in Food Budget 10 12 14 16 lnFX lowess cerealexp_share lnFX cerealexp_share Source: Author’s computation using ELIM-2006. Note: Households with zero expenditure on all cereals were excluded. As mentioned above, households get their food from three main sources: own-production, purchases from the market and “others” (gifts and ceremonies). The ELIM-2006 household budget survey reports consumption expenditures by mode of acquisition. However, it is not clear from the survey data whether consumption from own-production was valued at market prices or not. Furthermore, for purchased food expenditures, the data do not make a distinction between cereals consumption away from home and purchased food prepared at home. Summary statistics for individual cereals consumption will include the value of consumption from all the different sources of cereals supply. Table 4-16 below reports average annual expenditures per adult equivalent by cereal type and place of residence. National annual average expenditures are 25,125 CFAF/AE (46 US$/AE) 191 for rice; 14,769 CFAF/AE (27 US$/AE) for millet; 7,012 CFAF/AE (13 US$/AE) for sorghum and 4,505 CFAF/AE (8 US$/AE) for maize. A breakdown of cereals expenditures by place of residence shows that annual average rice expenditure in the urban areas is about double that of rural areas (Table 4-16) and average expenditure on rice in Bamako is larger than in other urban areas (Table 4-17). For millet, maize and sorghum, average expenditures per AE in the rural areas are much higher than those in urban areas. Up to 86% of the sample neither produces nor has any rice supplies from their own production. Table 4-16. Average Annual Expenditures (Including Value of Own-produced Grain) per Adult Equivalent by Cereal Type and Place of Residence Commodity National Urban (N=1566) (N=4454) Rice 25,125 35,697 (46) (66) Millet 14,769 11,606 (27) (21) Sorghum 7,012 4,435 (13) (8) Maize 4,505 3,286 (8) (6) Source: Author’s computation using ELIM-2006 Note: The figures in parenthesis are the US dollar equivalent. 192 Rural (N=2888) 19,392 (36) 16,485 (30) 8,410 (16) 5,166 (10) Table 4-17. Average Annual Expenditures (CFAF/AE) by Cereal Type and Place of Residence Bamako (N=399) Other urban (N=1167) Rural (N=2888) Rice 38,875 (72) 34,610 (64) 19,392 (36) Millet 11,455 (21) 11,658 (22) 16,485 (30) Sorghum 4,800 (9) 4,310 (8) 8,410 (16) Maize 3,172 (6) 3,324 (6) 5,166 (10) Source: Author’s computation using ELIM-2006 Note: The figures in parenthesis are the US dollar equivalent. Table 4-18 shows cereals expenditures per AE by income group and place of residence. The figures reveal an increase in rice expenditure per AE as per capita income increases irrespective of the place of residence. In both the rural and urban areas, millet expenditure per AE also increases from the low to the high income group. While rice expenditures per AE are higher in the urban areas than in the rural areas across all income groups, millet, maize and sorghum expenditures per AE on average are higher in the rural areas than in the urban areas. See also Figure 4-4 for the relationship between cereals expenditures per AE, income group and place of residence. The graph reveals that sorghum appears to be an inferior good for urban households. 193 Table 4-18. Average Annual Expenditures (CFAF/AE) by Cereal Type, by Income Group and Place of Residence Rice Millet Sorghum Maize 10,346 (19) 24,216 (45) 40,824 (76) 12,143 (22) 17,084 (32) 15,081 (28) 5,762 (11) 8,905 (16) 6,370 (12) 3,391 (6) 5,657 (10) 4,466 (8) 24,491 (45) 39,866 (74) 42,734 (79) 10,255 (19) 11,858 (22) 12,705 (24) 4,325 (8) 4,778 (9) 4,202 (8) 3,137 (6) 3,339 (6) 3,380 (6) 5,523 (10) 8,751 (16) 10,958 (20) 3,027 (6) 5,603 (10) 6,870 (13) National Low Middle High Urban Low Middle High Rural Low 7,890 11,557 (15) (21) Middle 18,134 17,321 (34) (32) High 32,166 20,580 (60) (38) Source: Author’s computation using ELIM-2006. Note: The figures in parenthesis are the US dollar equivalent. 194 Average Expenditure (CFA franc/AE) Figure 4-4. Cereals Expenditures (CFA franc/AE) by Income Group and Place of Residence 45,000 40,000 35,000 30,000 25,000 20,000 15,000 10,000 5,000 - Rice Millet Sorghum Maize low Middle High low Urban Middle High Rural Source: Author’s computation using ELIM-2006. Table 4-19 presents the budget share allocated to individual cereals types by place of residence and by income group. Rice is about 46% of the cereals budget considering the entire sample. Differences in individual cereals shares are quite pronounced between the urban and the rural areas. The mean share of rice in the cereals budget is 61% for the urban areas and 38% for the rural areas. Millet is second place to rice in terms of share in the cereals budget. However, the share of millet in rural areas is higher than that in urban areas. Nationwide and by place of residence, maize occupies the smallest position in the cereals budget. An examination of shares by cereal types, by income group and place of residence (Table 4-19 and Figure 4-5) reveals a consistent expenditure class-related pattern for rice, millet and sorghum consumption in both the rural and the urban areas, whereby the share of rice increases with income level while millet and sorghum shares decrease with increases in per capita income level. 195 Table 4-19. Shares in Cereal Budget by Cereal Type, Place of Residence and Income Group Sorghum Rice Millet Maize All 0.14 0.46 0.29 0.10 Low Middle High All 0.11 0.10 0.08 0.09 0.57 0.64 0.65 0.61 0.24 0.19 0.19 0.20 0.09 0.07 0.08 0.08 Low 0.18 0.27 Middle 0.17 0.36 High 0.16 0.46 All 0.17 0.38 Source: Author’s computation using ELIM-2006 0.43 0.35 0.29 0.34 0.11 0.12 0.10 0.11 National Urban Rural Figure 4-5. Shares in Cereal Budget by Cereal Type Place of Residence and Income Group 0.70 Expenditure shares 0.60 0.50 0.40 Sorghum 0.30 rice 0.20 Millet Maize 0.10 0.00 Low Middle High Low Source: Author’s computation using ELIM-2006 196 Middle High 4.7.2. Household Cereals Demand: Econometric Results Agricultural households are producers and consumers of food. Total output for agricultural households is usually split between the household’s own-consumption and marketable surplus (comprised of marketed surplus–the portion of production that is actually marketed—in conjunction with gifts and in-kind exchanges). Several studies have been carried out to understand how agricultural households make production and consumption decisions as well as the allocation of household production to sales and home consumption. Based on different assumptions, several arguments have been put forth on the responsiveness of own-consumption and marketed surplus to market prices. A key challenge is to estimate a complete demand system in a way consistent with the microeconomic behavior of rural Malian agricultural households that captures these households not only as food consumers, but also as food producers, operating under imperfect market situations. The agricultural household model originally proposed by Singh et al., (1986) helps to account for joint food consumption-production behavior, and the influence of influence of production decision on consumption is captured through the “profit effect”. Yan and Chern (2005), in the case of rural China, observed that production as well as market situations (imperfect market in most developing countries) affect the consumption decision of an agricultural household. As a result, they conclude that the marginal value of a food product consumed is the sale price if there is a net sale for this food item; it is the purchase price if there is a net purchase; and it is the shadow price if there is no purchase or sale. As mentioned earlier, the estimation of a complete demand model that takes into account how consumption decision is affected by production decision requires very detailed data which is not available in this case. Furthermore, giving that the ELIM-2006 data set reports the value of 197 consumption (expenditure) on each commodity by mode of acquisition, it is very likely that consumption from own-production was valued at market prices. Comparing aggregate expenditure on cereals to the revenue from cereals sales, most households in the data set are categorized as net cereals buyers. Thus, on the one hand, one could argue that amongst rural Malian households the decision to purchase cereals as well as the amount of cereals to be purchased is made conditional on the availability of cereals from own-production. On the other hand, it can also be argued that a household’s consumption from ownproduction does not go through the market and hence does not respond to market prices. Given that cereals are major staples in the current context, it is hard to think of households selling supplies from their own-production that were meant for household consumption due to high market prices to buy other food items. However, households could also sell one type of cereal – e.g., rice—and buy back a cheaper cereal, such as maize. To examine both arguments, the estimation of cereals demand was first carried out using total cereals expenditure (purchased and value of consumption from own production), and second using only purchased cereals expenditures and aggregating expenditures across purchased cereals . Although the results and discussions within this chapter focus on the first case, it makes reference to the second case (parameters reported in the Appendix). The estimation of household-level cereals demand involved three main steps. As observed by Bopape (2006), the results of the test for model specification are influenced by endogeneity in the total expenditure variable. Hence, the logical first step is to test for endogeneity of cereals expenditure. Second, a formal test for model specification is performed to determine the appropriateness of an AIDS or QUAIDS model. Third, the appropriate model is estimated dealing with zero expenditure and expenditure endogeneity. Demand elasticities are 198 reported by income group and by place of residence in order to understand differences in households’ cereals consumption behavior and any substitution between different cereal types. A formal test for endogeneity in total cereals expenditures is conducted using the augmented regression technique discussed earlier. The main challenge in the implementation of the technique is the choice of instrument that must fulfill the relevance and the exogeneity conditions of a good instrumental variable (IV). The relevance condition is that there must be sufficient correlation between the instrument and the potentially endogenous variable, while the exogeneity condition is that the instrument must not correlate with the error term in the demand model. The number of wives to the household head is used as an IV here. This IV is expected to be strongly correlated with total cereals expenditures in the sense that in Mali, the number of wives to the household head (HH) is a measure of wealth and wealthier households are expected to consume more cereals than households with fewer wives. The number of women in a household could also influence consumption choices. However, the inclusion of household adult equivalent as an additional explanatory variable in the demand model captures this additional effect. While the exogeneity condition of IVs is most often assumed, the relevance condition must be tested. To formally test the relevance of the instrument, two reduced forms were estimated–one for total cereals expenditure (lnCX) and the other for the square of total cereals expenditures ((lnCX)2). In each reduced form, the number of wives to the HHH (nwife) and nwife-squared were used as instruments. The estimated reduced forms with nwife and nwife squared are reported in Table 4-20. The R-squared for the reduced form for lnCX is 0.210 while that from the reduced form for (lnCX)2 is 0.2348. Following the estimation of the reduced forms, a test for the relevance of the instruments was conducted. The test is a joint test for the statistical 199 significance of nwife and nwife squared in each of the reduced forms. The test revealed that the number of wives to the HHH is sufficiently correlated with total cereals expenditure. In both reduced forms, we strongly reject (p-value =0.000) that nwife and nwife squared are jointly equal to zero in the equation of household’s cereals expenditures. Table 4-20. Estimated Reduced Forms for Cereals Expenditure and Cereal Expenditure Squared Variable (lnCX)2 lnCX Coef. -0.465 0.594 -0.499 0.167 0.320 -0.059 0.089 0.101 Std Err. 0.297 0.215 0.375 0.455 0.050 0.015 0.004 0.031 Price of rice Price of millet Price of sorghum Price of maize nwife nwife-squared HH Adult Equivalent Urban/Rural dummy Region dummies Kayes -0.024 0.143 Koulikoro -0.068 0.153 Sikasso -0.259 0.177 Segou -0.365 0.164 Mopti 0.007 0.151 Tombouctou 0.110 0.151 Gao 0.323 0.156 Bamako 0.142 0.148 Constant 12.937 1.881 R-squared 0.2101 Source: Author’s computation using ELIM-2006. Coef. -12.134 11.475 -14.799 9.910 7.293 -1.302 2.231 2.401 Std Err. 6.838 4.953 8.643 10.480 1.153 0.354 0.082 0.721 -0.467 -1.251 -6.023 -8.544 0.137 2.281 7.911 3.758 171.086 3.299 3.537 4.071 3.778 3.474 3.479 3.603 3.407 43.347 0.2348 The residual-based procedure is used to test for the endogeneity of cereals expenditure in the budget share equations (see Wooldridge (2002): 118-122). The procedure for carrying out endogeneity tests involves augmenting the budget share equation for each cereal type with residuals from the reduced forms for cereals expenditure, then testing for the statistical significance of the coefficient on the residuals. The null hypothesis is that cereals expenditure is 200 exogenous. Blundell and Robin's (1999) approach that includes only the residuals from the reduced form for lnCX, using the number of wives to the HHH and its square as instruments, is applied here. Table 4-21 reports results of these Chi-square (χ2) tests, first in the individual budget share equations, and then across all budget share equations in the demand system. In the individual budget share equations, the test results provide statistical evidence in favor of cereals expenditure exogeneity in all four budget share equations. The test was carried out on the system of equations with (restricted) and without (unrestricted) imposing demand restrictions (symmetry, and homogeneity with adding-up satisfied automatically by the data) during estimation. The null hypothesis is that cereals expenditure is exogenous across all budget share equations in the demand model in both the restricted and unrestricted system. The restricted test gives a Chi-square (χ2) statistic of 4.78 (p= 0.1883). The conclusion is that we fail to reject cereal expenditure exogeneity at 5%. This implies that in the case of system estimation of the budget share equations, it is not necessary to control for expenditure endogeneity. With total cereals expenditure exogenous, the only necessary modification to the QUAIDS model was to deal with the issue of zero-expenditures. Table 4-21. Results of the Test for the Endogeneity of Expenditure Equation-by-equation tests Commodity t stat Rice 0.01 Millet 0.83 Maize 2.07 Sorghum 0.01 Equation System tests (across all budget shares): SUR Unrestricted 2.51 Restricted 4.78 Source: Author’s computation using ELIM-2006. 201 p-value 0.9753 0.3628 0.1508 0.9107 0.4730 0.1883 Bopape's (2006) test for model specification was implemented with total cereals expenditure. The translog price aggregator, a(p), is linearized with the Stone's price index for the purpose of testing. The results of the model specification test are reported in Table 4-22. The test was carried out on individual budget share equations and on the overall system (with and without demand restrictions). In each of the share equations, we reject the null hypothesis that coefficient of the price times expenditure terms are jointly equal to zero. Performing the tests on the system still produce results in favor of the quadratic almost ideal demand model. Hence, based on these test results, our preferred estimates are the results of the QUAIDS model. Table 4-22. Tests for Nonlinearity of the Demand System Based on Statistical Significance of the Coefficient of the Price Times Expenditure-Squared Terms Equation-by-equation tests Commodity t stat Rice 13.86 Millet 7.66 Maize 18.33 Sorghum 3.94 Equation System tests (across all budget shares): SUR Unrestricted 142.52 Restricted 189.36 Source: Author’s computation using ELIM-2006. p-value 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 The final specification of the demand model is also influenced by the presence of zeroexpenditure (selection bias). Rice, millet and sorghum are the mainstays of the Malian diet. Zero expenditure of these commodities could be the result of the reference period used in reporting consumption failing to capture any expenditure on some of these commodities. As shown on Table A4-1 in the Appendix, considering the total cereals expenditures (purchased plus the value 202 of own-consumption)37, 5.1% of the total sample reported zero expenditure on rice, 45.2% reported zero expenditure on sorghum, 18.9% reported zero expenditure on millet and 49.8% reported zero expenditure on maize. Therefore, to check if any fundamental difference exists between the decisions to purchase these cereals and how much of each to purchase, the QUAIDS model for cereals demand is estimated dealing with zero-expenditure (censored). The general procedure in the estimation of the censored QUAIDS model in the absence of any expenditure endogeneity is as follows: we estimate the household’s decision to consume a specific cereal type (Equation 4-3) by using a maximum likelihood probit regression to obtain household-specific probit estimates σ ̂h zih . The univariate standard normal probability density (pdf) and the cumulative distribution (cdf) to use in the QUAIDS model are later calculated for each cereal type and each household. Given the initial values of the price index a(p) and the predicted values (pdfs and cdfs) from the probit regressions, the cross-equation nature of the restrictions, and the non-linear structure of the QUAIDS model, Poi’s (2008) “demand-system estimation: update, Non-Linear Seemingly Unrelated regression (NLSUR) model” written in STATA, augmented with the pdf and cdf from the first stage probit regression to account for zero expenditure and household demographics, is used to estimate the demand system in equation 4-5 ( dropping the term 𝜌𝑠 𝜏𝑠𝑖 since we rejected expenditure endogeneity). Disaggregating zero expenditures by mode of acquisition, it is observed that 27% of the households purchased sorghum in the reference period, 80% had positive purchases for rice, 51% purchased millet and 19% purchased maize in the reference period. For rice for instance, the percentage zero expenditure drops from 20% (considering only purchased cereals expenditures) to 5.1% (considering total cereals expenditures (purchased plus value of own consumption) in the reference period. Thus, some households may not have purchased rice but they consumed rice from their own production. 203 37 4.7.2.1. Expenditure Elasticities by Place of Residence Table A4-4 reports the estimated parameters from a censored QUAIDS regression by place of residence using total cereals expenditures. Table A4-5 also reports the estimated elasticities and their standard errors by place of residence using total cereals expenditures. Estimates of expenditure elasticities for the urban and rural areas (considering all per capita income groups within a place of residence) are reported in Table 4-23 below. All expenditure elasticities are positive and statistically significant at a 1% level for all four cereals types in the rural and urban subsamples, indicating that these commodities are normal goods. Considering the urban subsample, rice and maize are expenditure inelastic, while millet and sorghum are expenditure elastic. The high expenditure elasticity for millet and sorghum in the urban area is intriguing because these are not only staple foods, but also, as pointed out by past studies, coarse grains are generally less preferred in the urban areas for various reasons such as the high opportunity cost of the time required for their processing/preparation. Moreover, the ELIM-2006 dataset does not distinguish between consumption away from home or the form (processed or unprocessed) in which these coarse grains are consumed. In the rural area, in addition to millet and sorghum (as in the urban area), maize is also expenditure elastic– indicating a more than proportionate increase in expenditure from an increase in total cereals budget. Comparing the urban and the rural subsamples, the expenditure elasticity for rice is higher amongst the urban households than the rural households. The higher rice expenditure elasticity in the urban area (0.964) than in the rural areas (0.728) indicates that urban households are more likely to spend any additional income on rice than are rural households. This, in spite of the already greater rice consumption shares in urban areas compared to rural areas as revealed by 204 the descriptive statistics of the data; theaverage rice consumption level and share amongst urban households are quite high (about double those of rural areas). The estimated urban rice expenditure elasticity is higher than what Camara (2004) estimated as rice income elasticity (0.796) for Bamako households only and much larger than what Rogers and Lowdermilk (1991) obtained as rice income elasticity (0.562) for urban Mali (the cities of Kayes, Sikasso, Segou, Tombouctou, Gao, Bamako, Mopti, and Koulikoro). The growing positive expenditure elasticity of rice over time supports Camara’s comment that rice is becoming less of a necessity for urban households over time. Thus, for rice and sorghum, we observe higher expenditure elasticities in the urban areas than in the rural areas, while millet and maize expenditure elasticities are higher in the rural areas than in the urban areas. Estimated parameters by place of residence using only purchased cereals expenditures are also reported in Table A4-8 and A4-9 in Appendix38. 4.7.2.2. Expenditure Elasticities by Income Group within Place of Residence Expenditure elasticities are further examined by income-group per place of residence to determine if there are income-group related differences within a specific location (Table 4-23). Tables A4-6 and A4-7 also show the full matrix of estimated parameters and elasticities by income group within place of residence, using total cereals expenditures (purchased plus the value of own-consumption). In the urban and rural areas and across all income groups, all the expenditure elasticities are statistically significant at 1%39 and positive as expected for The test for endogeneity using only purchased cereals expenditure revealed that purchased cereals expenditure was endogenous. Hence, the estimation of cereals demand using purchased cereals expenditure was carried out after correcting for endogeneity in purchased cereals expenditure using the approach outlined earlier. 38 39 Except for the low-income urban households, where millet expenditure elasticity is positive but statistically significant at a 10% level of significance. 205 necessities. In both rural and urban subsamples, no clear pattern is observed from the low to the middle and to the high income groups. Thus, for clarity, comparison will be made mostly between the low-income and the high-income groups. Table 4-23. Cereals Expenditure Elasticities by Place of Residence and Income Group Rice All 0.964* Low Middle High 1.248* 0.880* 1.239* All Rice 0.728* Millet Urban 1.038* By Income Group 0.758*** 1.079* 0.415* Rural Millet 1.200* By Income Group 1.248* 0.980* 1.025* Maize Sorghum 0.668* 1.502* 0.702* 1.070* 1.032* 0.673* 1.454* 1.247* Maize 1.099* Sorghum 1.109* Low 0.654* 1.030* 1.054* Middle 1.006* 0.867* 1.069* High 1.001* 1.014* 0.974* Source: Author. Note: * means significant at a 1% level and ** means significant at 5% and *** means significant at 10%. In the urban area, rice expenditure elasticity decreases slightly from the low- to the highincome urban group, millet expenditure elasticity drops from the low- to the high-income group, and maize and sorghum elasticities increase from the low- to the high-income urban groups. The noticeable decline in millet expenditure elasticity from the urban low- to the urban highincome groups indicates that as households get richer in the urban area, they are less likely to spend any additional income on millet. The increase in sorghum expenditure elasticity between the urban low- (0.673) and the urban high-income (1.247) illustrates that the sorghum expenditure elasticity observed in the urban area aggregating across all income groups (1.501 ) 206 is largely driven by the behavior of the urban middle- and high-income groups. Hence, in terms of expenditure elasticities, in the urban area, we observe a high preference for rice and sorghum at higher per capita income levels while the preference for millet seems to decrease with income level. The high expenditure of elasticity of sorghum as income increases calls for attention and warrants further investigation into the type or form in which sorghum is consumed in the urban area. There is a need to differentiate demand for sorghum of different quality (processed and unprocessed) and by place of consumption (for example, home and away from home). Rural households also reveal high expenditure elasticities across all income groups for all the different cereals when total cereals expenditures are used. The responsiveness of rice to changes in income increases from the low- to the high-income households. Millet, sorghum and to a lesser extent maize expenditure elasticities tend to decline from the rural low- to the highincome rural group. Overall, using total cereals expenditures, the hypothesis that poorer households have higher expenditure elasticities is true for millet, sorghum and to a lesser extent maize in the rural areas and millet in the urban areas. From the summary statistics (Table 4-19), we observe a clear pattern of decline in sorghum and millet budget shares from the low- to the high-income groups and a marked increase in the rice budget share from the rural low- to high-income households. Expenditure elasticities by income group and place of residence estimated using only purchased cereals expenditures are also reported in Tables A4-10 and A4-11. 4.7.2.3. Own-Price Responses by Place of Residence Table 4-24 reports uncompensated and compensated own-price elasticities of cereals demand by place of residence using total cereals expenditures (purchased plus value of own-consumption). 207 Table A4-5 in Appendix also reports the standard errors of the estimated elasticities. All uncompensated and compensated own-price elasticities are not only statistically significant at a 5% level, but are also negative in both the urban and the rural sub-samples, thus supporting a downward sloping demand curve. Considering the urban area (without disaggregating by income group), all uncompensated own-price elasticities are close to unity, indicating high sensitivity to own price changes. The own-price elasticity for rice obtained here for the urban area (-0.955) are about 3 times that reported by Camara (2004) using data for Bamako households only (-0.338). However, Rogers and Lowdermilk (1991) using urban Malian data found the own-price elasticity of demand for rice to be -0.683. Given that the urban sample used by Rogers and Lowdermilk (1991) is quite comparable to that used in this study (in terms of geographical coverage), it can be noted that the sensitivity of rice demand to changes in its own-price in the urban areas appears to have increased over two decades. When the substitution effects are considered, all the cereals became less elastic, as the urban compensated own-price elasticities get smaller in magnitude than uncompensated own-price elasticities, as expected for normal goods. Considering total cereals expenditures, millet demand is the least sensitive to changes in its own price in the urban area. Thus, the hypothesis that rice is the least responsive to changes in its own price in the urban area due to the high opportunity cost of time and demand for convenience by urban time-poor consumers is rejected. Notwithstanding, compared to maize and sorghum, rice demand is less responsive to changes in its own price. Still using total cereals expenditures and without disaggregating by income group, in the rural area, all statistically significant uncompensated own-price elasticities are negative as expected. Rice is the least sensitive to changes in its own price in the rural area. The estimated 208 elasticities using only purchased cereals expenditures are shown in Tables A4-8 and A4-9 in Appendix. Table 4-24. Cereals Own-Price Elasticities - By Place of Residence and Income Group Rice Millet Maize Sorghum URBAN All Low Middle High -0.955* -0.997* -0.915* -1.065* All Low Middle High -0.341* -0.277* -0.318* -0.241* Uncompensated -0.904* -1.046* -0.243 -0.996* -1.035* -1.026* -0.514* -0.946* Compensated -0.714* -0.986* -0.089 -0.914* -0.860* -0.945* -0.439* -0.870* -1.156* -1.014* -0.948* -0.658* -1.021* -0.944* -0.828 -0.557** RURAL All Low Middle High -0.938* -0.781* -0.973* -0.991* Uncompensated -1.135* -1.024* -1.010* -1.041* -0.963* -0.940* -0.993* -0.996* Compensated -0.723* -0.896* -0.513* -0.907* -0.622* -0.834* -0.696* -0.897* -0.994* -0.894* -0.945 -0.988* All -0.660* -0.819* Low -0.585* -0.713* Middle -0.607* -0.768* High -0.516* -0.853* Source: Author. Note: * = significant at 1%, ** =significant at 5% and *** = significant at 10%. 209 4.7.2.4. Own-Price Responses by Income Group within Place of Residence Using total cereals expenditures and differentiating by urban-income groups, all the uncompensated own-price responses (except millet in the low-income group) and compensated own-price responses (except millet in the low-income and sorghum in the middle-income) are statistically significant and have the expected negative sign (Table 4-24 above). In terms of uncompensated elasticities, millet and sorghum are the least own-price sensitive amongst the urban high income group; rice is the least own-price sensitive amongst the middle-income urban group; and rice and maize are the least own-price sensitive amongst the low-income urban group. Comparing the estimates for the low- and high-income urban groups, we observe that the hypothesis that the own-price elasticities of cereals demand are more elastic (larger in absolute terms) for lower income households than higher income households is validated only for maize and sorghum. Rice own-price elasticities are higher for high-income urban households than the low-income urban households. In the rural areas, in terms of uncompensated own-price elasticities, low-income households are more sensitive to a change in the price of millet and maize than high-income households. 4.7.2.5. Cross Price Elasticities by Place of Residence The compensated cross-price elasticities by place of residence (aggregated across all income groups) and using total cereals expenditures are reported in Table 4-25. In the urban area, all the cross-price effects are positive and statistically significant, implying a relationship of substitution amongst the different cereals types. The high and positive cross-price elasticities of millet (0.563) and sorghum (0.627) demand with respect to a change in price of rice supports previous findings, e.g., Camara (2004), that urban households would run towards purchasing more 210 sorghum and millet in the face of high rice prices. In contrast, Rogers and Lowdermilk (1991) found that changing rice prices did not have a statistically significant impact on millet-sorghum purchases. The authors attributed their result to the fact that rice and millet-sorghum occupied different functions in urban households’ diets, resulting in a tendency amongst households to consume rice at mid-day while millet and sorghum were consumed in the morning and evening. The difference with the Rogers-Lowdermilk findings may also reflect a shift in consumption habits where rice is increasingly eaten in the evenings as well. Therefore, for the range of prices observed in 2006, the price of rice appears to have a significant effect on the consumption of coarse grains in the urban area. In the rural area, with the exception of the relationship between rice and sorghum, all other compensated cross price effects are positive and statistically significant, indicating a relationship of substitution between the different cereals. Table 4-25. Compensated Cross-Price Elasticities - By Place of Residence Urban lnprice lnpmillet lnpmaize lnpsorghum Rice -0.341* 0.168* 0.084* 0.068* Rice -0.660* 0.420* 0.095* 0.003 Millet 0.563* -0.714* 0.081* 0.137* Rural Millet 0.491* -0.723* 0.109* 0.291* Maize 0.446* 0.206* -0.986* 0.186* Sorghum 0.627* 0.218* 0.276* -1.021* Maize 0.609* 0.116* -0.896 0.208* Sorghum 0.133 0.543* 0.148* -0.819* lnprice lnpmillet lnpmaize lnpsorghum Source: Author. Author * means significant at a 1%; ** significance at 5%, and *** means significant at 10%. 211 Comparing cross-price effects between the urban and the rural areas when total cereals expenditures are used, we observe that in both the urban and rural areas, millet and maize are substitutes for rice. However, millet is a stronger substitute for rice than maize in the urban area, while maize is a stronger substitute for rice than millet in the rural area. Sorghum substitutes rice only in the urban area. The stronger substitution of millet and sorghum for rice in the urban area could reflect the greater availability of processing services (small mills) for coarse grains in urban areas than in rural areas. Urban households, especially those in larger cities, also quite often have a full panoply of goods available in the markets. This availability of a wider range of products to draw from could also explain the larger substitution effects amongst urban households. Estimated cross-price elasticities using only purchased cereals expenditures are also reported in Tables A4-8 and A4-9 in Appendix. 4.7.2.6. Cross Price Elasticities by Place of Residence and Income Group 4.7.2.6.1. Urban Cross Price Effects by Income Group Table 4-26 shows compensated cross-price elasticities in the urban areas by income group using total cereals expenditures. Amongst the low-income group, maize and sorghum are substitutes for rice with elasticities of substitution of 0.567 and 0.460 respectively. In the middle-income group, millet, maize and sorghum are substitutes for rice, with elasticities of substitution of 0.674, 0.580 and 0.437 respectively. Amongst high-income urban households, the relationship between a change in the price of rice and the demand for millet and sorghum is not statistically significant. Maize is a substitute for rice amongst the high-income urban group, with a high cross price elasticity of 1.299. 212 Comparing across urban income groups, we observe that: (i) the degree of substitution of rice for millet is almost similar in the low- and high-income groups; (ii) substitution of rice for sorghum is stronger in the low-income than the high-income group; (iii) substitution of rice for maize is of almost similar magnitude across all income groups; (iv) substitution of maize for rice increases from the low- to the high-income group; (v) substitution of maize for sorghum drops from the low- to the high-income group; and (vi) the degree of substitution of sorghum for rice drops from the low- to the middle-income group. Tables A4-10 and A4-11 in Appendix report estimated parameters by urban income groups using only purchased cereals expenditures. Table 4-26. Urban Compensated Cross-Price Elasticities by Income Group lnprice lnpmillet lnpmaize lnpsorghum Rice -0.277* 0.129** 0.098* 0.130* lnprice lnpmillet lnpmaize lnpsorghum Rice -0.318* 0.146* 0.096* 0.067* Rice -0.241* 0.128* -0.097** 0.089* Low-Income Millet Maize 0.192 0.567* -0.089 0.145 0.124*** -0.914* -0.077 0.215** Middle-Income Millet Maize 0.674* 0.580* -0.860* 0.191* 0.063* -0.945* 0.128* 0.111* High-Income Millet Maize 0.305 1.299* -0.439* 0.570*** 0.651* -0.870* -0.034 0.245 Sorghum 0.460* -0.304 0.300* -0.944* Sorghum 0.437* 0.356* 0.000* -0.828* Sorghum 0.167 0.089 -0.005 -0.557** lnprice lnpmillet lnpmaize lnpsorghum Source: Author. Note: * means significant at a 1%; ** significance at 5%, and *** means significant at 10%. 213 4.7.2.6.2. Rural Cross Price Effects by Income Group Table 4-27 shows the compensated cross-price elasticities across income groups in the rural areas using total cereals expenditures. All compensated cross-price elasticities are statistically significant, and a relationship of substitution exists between the different cereals in the lowincome and high-income rural group. Also in the middle-income rural group, a relationship of substitution characterizes all statistically significant cross-price effects. Comparing across rural income groups, we notice that the sensitivity of rice demand to changes in the price of millet, maize and sorghum increases from the low- to the middle-income rural group but drops from the middle- to the high-income rural group. Also noticeable is the increase in the sensitivity of millet, maize and sorghum demand to changes in the price of rice as per capita income increases. This means that richer rural households are more likely to substitute coarse grains for rice when the price of rice increases. The compensated cross-price elasticities across income groups in the rural areas estimated using only purchased cereals expenditures are reported in Tables A4-10 and A4-11 in Appendix. 214 Table 4-27. Rural Compensated Cross-Price Elasticities by Income Group lnprice lnpmillet lnpmaize lnpsorghum Rice -0.585* 0.291* 0.058* 0.148* Millet 0.215* -0.513* 0.202* 0.176* lnprice lnpmillet lnpmaize lnpsorghum Rice -0.607* 0.335* 0.119* 0.167* Millet 0.347* -0.622* 0.122* 0.171* Rice -0.516* 0.286* 0.096* 0.141* Millet 0.457* -0.696* 0.104* 0.136* Low-Income Maize 0.326* 0.469* -0.907* 0.117* Middle-Income Maize 0.338* 0.363* -0.834* 0.048 High-Income Maize 0.451* 0.308* -0.897* 0.136* Sorghum 0.369* 0.298* 0.103* -0.713* Sorghum 0.369* 0.367* 0.064 -0.768* Sorghum 0.495* 0.266* 0.092* -0.853* lnprice lnpmillet lnpmaize lnpsorghum Source: Author. Note: * means significant at a 1%; ** significance at 5%, and *** means significant at 10%. 4.8. Chapter Summary The goal of this chapter was to provide micro-level evidence on food consumption in Mali using household budget survey data of 2006. Specifically, the analysis sought to determine the factors that influence the demand for individual cereals and the substitution among them; and to provide separate cereals demand estimates by income groups and by place of residence. A censored QUAIDS model is estimated to understand the factors influencing the demand for individual cereal types (rice, millet, maize and sorghum). The model is estimated (a) using total cereals expenditures (the sum of purchased cereals and the value of consumption from 215 own-production), and (b) using only purchased cereals expenditures. The estimated parameters under scenario (b) are reported in the appendix. Positive expenditure elasticities were found for all four cereals type, irrespective of place of residence. Using total cereals expenditure, rice and sorghum expenditure elasticities were found to be higher in the urban area than in the rural areas, while millet and maize expenditure elasticities are higher in the rural areas than in the urban areas. Comparing rice expenditure elasticity estimated for the urban area in this study to that reported by previous studies in Mali (e.g., Camara, 2004), we observe a positive trend over time and find support for Camara’s assertion that rice is becoming less of a necessity for urban households over time. The high expenditure elasticity of sorghum in the urban area calls for further investigations into the quality of sorghum that is consumed, since it is often argued that coarse grains (such as sorghum) are more time consuming and less convenient for urban time poor consumers. The analysis of expenditure elasticities by income-group and place of residence also reveals some income group-related pattern for rice and millet and to a lesser extent sorghum in the urban area. Using total cereals expenditures, we observe in the urban area a high preference for rice and sorghum at higher per capita income levels while the preference for millet seems to decrease with income level. The high expenditure elasticity of sorghum as income increases indicates a need to differentiate sorghum demand by quality (processed and unprocessed) and by place of consumption (for example, home and away from home). While the expenditure elasticity for millet decreases with increases income amongst urban households, amongst rural households, millet, sorghum and to a lesser extent maize expenditure elasticities tend to decline from the rural low- to the high-income households. This suggests declining preference for coarse grains as rural households get richer. 216 Uncompensated and compensated own-price elasticities by place of residence support a downward-sloping demand curve for all cereals. Considering total cereals expenditures and without disaggregating by income groups, the hypothesis that rice is the least responsive to changes in its own price in the urban area due to the high opportunity cost of time and demand for convenience by urban-poor consumers is rejected. Millet is the least sensitive to changes in its own price in the urban areas. Rice is the least sensitive to changes in its own price in the rural area. The analysis of own-price elasticities by income group and place of residence using total cereals expenditures reveal that amongst urban households, only maize and sorghum support the hypothesis that the own-price elasticities of cereals demand are more elastic (larger in absolute terms) for lower income households than higher income households. High-income urban households were found to have higher own-price elasticities for rice than the low-income urban households. In the rural areas, low-income households were more sensitive to a change in the price of millet and maize than high-income households. The analysis also reveals that a relationship of substitution characterizes most statistically significant cross-price effects. Using total cereals expenditures and aggregating all income groups, in the urban areas we observe high and positive cross-price elasticities of millet and sorghum demand with respect to a change in the price of rice. This finding supports previous findings (e.g., Camara, 2004), that urban households would run towards purchasing more sorghum and millet in the face of high rice prices. Compensated cross-price elasticities in the rural areas also indicate a relationship of substitution between the different cereals. Furthermore, comparing the urban and the rural areas in terms of the magnitude of crossprice effects, we observe a stronger substitution of millet and sorghum for rice amongst urban 217 households. This could reflect the greater availability of processing services (small mills) for coarse grains in urban areas, as well as the fact that urban markets, especially in larger cities, also quite often make a wider range of products available to consumers. Compensated cross-price elasticities by income group in the urban area using total cereals expenditures reveal that amongst urban households, while the degree of substitution of rice for millet is almost similar in the low- and high-income groups, the degree of substitution of rice for sorghum is stronger in the low-income than the high-income group. The substitution of maize for rice increases from the low- to the high-income group, while the substitution of maize for sorghum drops from the low- to the high-income group. Comparing across rural income groups and using total cereals expenditures, we notice an increase in the sensitivity of millet, maize and sorghum demand to changes in the price of rice as per capita income increases. This means that richer rural households are more likely to substitute coarse grains for rice when the price of rice increases. The preceding analysis reveals high substitution between rice and coarse grains in both the rural and the urban areas and across income groups. This finding implies some scope for dealing with price spikes for one cereal by increasing the availability of substitutes—a possibility that the earlier findings of low cross-elasticities seemed to discount. 218 APPENDIX 219 Table A4-1. Structure of ELIM-2006 data Region 1. KAYES Cercle 1. Kayes 2. Bafoulab é 3. Diéma 4. Kéniéba 5. Kita 6. Nioro 7. Yélimané Arrondissement Kayes central Ambidedi Aourou Diamou Sadiola Same Segala Kayes Bafoulabe central Bamafele Diakon Goundara Koundian Mahina Bafoulabe central Bamafele Diakon Goundara Diema central Bema Diangountecamar Dioumara Lakamane Kenieba central Faraba Kita central Djidian Kokofata Sebekoro Sefeto Sirakoro Toukoto Kita Nioro central Gavinane Simbi Troungoumbe Nioro Yelimane central Kirane 220 Market with available prices Kayes Centre KayesN'Dy Kayes Plateau Diéma Badinko Kita Nioro Table A4-1. (cont’d) Region Cercle Arrondissement Market with available prices Tambacara 2. KOULIKOR O 8. Koulikor o Koulikoro central Koula-koulikoro Niamina Sirakorola Tougouni Commune Koulikoro 9. Banamba Banamba central Boron Toubacoura Toukoroba 10. Dioila Dioila central Banco Beleko Fana Massigui Mena 11. Kangaba Kangaba central Narena 12. Kati Kati central Baguineda Kalabancoro Kourouba Neguela Ouelessebougou Sanankoroba Siby Kati 13. Kolokani Kolokani central Djidieni Massantola Nonssombougou 14. Nara Nara central Balle Dilly Fallou 221 Sirakorola Koulikoro Ba Koulikoro Gare Dioïla Fana Nara Table A4-1. (cont’d) Region 3. SIKASSO Cercle Arrondissement 15. Sikasso Sikasso central Blendio Danderesso Dogoni Kignan Klela Niena N'kourala Commune sikasso 16. Bougoun Bougouni central i Dogo-bougouni Faragouaran Garalo Koumantou Manankoro Sanso Zantiebougou Commune bougouni 17. Kadiolo Kadiolo central 18. Kolondi éba 19. Koutiala 20. Yanfolil a 21. Yorosso Fourou Kolondieba central Fakola Kadiona Kebila Konsseguela Molobala M'pessoba Commune koutiala Yanfolila central Doussoudiana Kangare Siekorole Yorosso central Kouri 222 Market with available prices Sikasso Centre SikassoMédine Bougouni Koumantou Loulouni -in cercle but not in this arrondissement Koutiala M'Pèssoba Zangasso (in cercle but not exactly in this arrondissement Koury Table A4-1. (cont’d) Region Cercle 4. SÉGOU 22. Ségou Arrondissement Segou central Sinzana Dioro Doura Katiena Markala Sansanding Ségou 23. Baraouel Baroueli central i Sanando Tamani 24. Bla Bla central Diaramana Falo 25. 26. Macina Niono Touna Yangasso Macina central Kologotomo Monipe Sarro Saye Niono central Nampala Sokolo 27. 28. San Tominia n San central Dieli Kassorola Kimparana Sourountouna Sy San Tominian central Fangasso Koula Mafoune Tamissa 223 Market with available prices Ségou Centre Dioro Fatiné-in this cercle Ségou Château Shiango Bla Dougouolo (in this cercle but in this arrondissement Touna Macina Monimpébougou Niono Dogofri-in this cercle but not exactly in this arrondissement Sokolo Diakawèrè in Cercle but not in arrondissement-inMariko-Niono Table A4-1. (cont’d) Region Cercle 5. MOPTI 27. Mopti 28. Bandiaga 29. Bankass Arrondissement Mopti central Dialloube Fatoma Konna Korientze Ouromodi Mopti Bandiagara central Kani-gogouna Kendie Sangha Dialassagou Segue Sokoura 30. 31. Djénné Douentza 32. Koro 33. Ténenkou 34. Youvarou Djenne central Konio Kouakourou Mougnan Sofara Douentza central Hombori Koro central Diankabou Dinangourou Dioungani Koporokeniena Madougou Tenenkou central Dioura Sossobe Toguerecoumbe Youvarou central 224 Market with available prices Mopti Digue Bandiagara Diallassagou Bankass in Cercle but not in arrond- in arrond of Bankass Koulogon in Cercle but not in arrondissement Djenne MoptiGuangal Table A4-1. (cont’d) Region 6. TOMBOUCTO U Cercle 37. Tombouct ou 38. 39. Diré Gounda m Gourma r 41. Niafunk é 40. 7. GAO 42. Gao Ansong o 44. Bourem 43. 8. 9. KIDAL BAMAKO DISTRICT 45. Ménaka 46. Kidal 47. Téssalit 48. Bamako Arrondissement Tombouctou central Aglal Boureminaly Commune tombouct Diré central Sareymou Goundam central Bintagoundou Douekis Tonka Gourma-rharous Gossi Niafunke central Lere Sarafere Soumpi Gao central Haoussafoulane Gao Ansongo central Tessit Bourem central Bamba Temera Menaka central Annefis Kidal Tessalit central Aguel-hoc Commune i Commune ii Commune iii Commune iv Commune v Commune vi Market with available prices Tombouctou Diré Tonka Léré Gao Ansongo Kidal Fadjiguila Niarela, Medine Dibida, Lafiabougou Badalabougou, Djikoroni Faladié, Magnambougou, Sogoniko, Niamakoro Ouolofobougou Source: Author. 225 Table A4-2. Number of Zero Expenditures by Place of Residence-Considering Expenditure on All Modes of Acquisition Cereal type Sorghum Rice Millet Maize Place of Residence Urban Rural Total Urban Rural Total Urban Rural Total Urban Rural Total Zero Expenditure 910 1101 2011 53 172 225 388 455 843 942 1277 2219 Positive Expenditure 656 1787 2443 1513 2716 4229 1178 2433 3611 624 1611 2235 Percent non Expenditure 45.3 54.7 45.2 23.6 76.4 5.1 46.0 54.0 18.9 42.4 57.6 49.8 Source: Author. Table A4-3. Zero-Expenditure by Mode of Acquisition Cereal Type Zero Positive HomeHomeProduced Produced Sorghum 3270 1184 Rice 3837 617 Millet 3163 1291 Maize 3166 1288 Source: Author. Percentage zero HomeProduced 73% 86% 71% 71% 226 Zero purchase Positive purchase 3249 901 2201 3600 1205 3553 2253 854 Percentage Positive purchase 27% 80% 51% 19% Table A4-4. Estimated Parameters of the Censored QUAIDS Model for Cereals Demand by Place of Residence – Total Cereals Expenditure Coef. Urban Std. Err. Coef. Rural Std. Err. P>|z| P>|z| Constants α1 0.622 0.028 0.000 0.874 0.069 0.000 α2 0.229 0.045 0.000 -0.047 0.100 0.637 α3 0.293 0.089 0.001 -0.287 0.077 0.000 α4 -0.606 0.151 0.000 -0.189 0.101 0.060 Expenditure β1 -0.051 0.011 0.000 -0.206 0.017 0.000 β2 0.034 0.012 0.007 0.148 0.028 0.000 β3 -0.088 0.009 0.000 0.054 0.011 0.000 β4 0.110 0.028 0.000 0.021 0.025 0.407 Prices γ11 0.014 0.005 0.011 -0.118 0.029 0.000 γ12 -0.012 0.006 0.057 0.107 0.034 0.001 γ13 -0.016 0.005 0.003 0.053 0.014 0.000 γ14 -0.005 0.009 0.599 -0.039 0.024 0.106 γ22 -0.012 0.006 0.057 0.107 0.034 0.001 γ23 0.024 0.008 0.005 -0.076 0.035 0.031 γ24 0.001 0.006 0.815 -0.049 0.019 0.010 γ33 0.007 0.010 0.497 0.036 0.025 0.145 γ34 -0.016 0.005 0.003 0.053 0.014 0.000 γ44 0.001 0.006 0.815 -0.049 0.019 0.010 Note: Rice=1, millet=2, maize= 3 and sorghum=4. γij= Equation i and commodity j. 227 Table A4-4 (cont’d) Urban Rural Expenditure Squared λ1 0.009 0.001 0.000 0.020 0.001 0.000 λ2 -0.008 0.001 0.000 -0.014 0.002 0.000 λ3 0.005 0.001 0.000 -0.007 0.001 0.000 λ4 -0.004 0.002 0.014 0.002 0.002 0.471 PDFs Rice 0.338 0.039 0.000 0.567 0.043 0.000 Millet 0.283 0.024 0.000 0.155 0.042 0.000 Maize 0.165 0.081 0.041 0.290 0.040 0.000 Sorghum 0.546 0.077 0.000 0.490 0.045 0.000 HH Adult Equivalent Rice 0.004 0.001 0.000 0.002 0.001 0.002 Millet -0.005 0.001 0.000 -0.003 0.001 0.000 Maize 0.001 0.001 0.210 -0.002 0.000 0.000 Sorghum 0.001 0.001 0.460 0.001 0.000 0.010 Source: Author. Note: Rice=1, millet=2, maize= 3 and sorghum=4. γij= Equation i and commodity j. 228 Table A4-5. Estimated Elasticities of the Censored QUAIDS Model for Cereals Demand by Place of Residence - Total Cereals Expenditures Urban Coef. Std. Err. P>|z| Coef. Rural Std. Err. 0.000 0.000 0.000 0.000 0.728 1.200 1.099 1.109 0.031 0.044 0.034 0.060 0.000 0.000 0.000 0.000 0.009 0.000 -0.938 0.029 0.000 0.011 0.008 0.014 0.025 0.370 0.571 0.004 0.002 0.192 0.018 -0.172 0.028 0.050 0.021 0.037 0.036 0.000 0.388 0.000 0.429 0.037 0.023 0.042 0.018 0.000 0.330 0.086 0.646 -1.135 -0.046 0.138 0.112 0.059 0.030 0.048 0.038 0.000 0.124 0.004 0.003 0.024 0.030 0.048 0.041 0.064 0.000 0.018 0.000 -0.174 -1.024 0.031 -0.189 0.074 0.037 0.060 0.053 0.019 0.000 0.603 0.000 0.049 0.046 0.087 0.489 0.001 0.000 0.120 0.021 -0.994 0.087 0.046 0.073 0.167 0.641 0.000 P>|z| Expenditure Elasticities Rice 0.964 Millet 1.038 Maize 0.668 Sorghum 1.502 Uncompensated Elasticities Rice Rice -0.955 equation Millet -0.010 Maize -0.005 Sorghum -0.041 Millet Rice -0.077 Equation Millet -0.904 Maize -0.022 Sorghum 0.072 Maize Rice 0.008 Equation Millet 0.045 Maize -1.046 Sorghum 0.113 Sorghum rice -0.155 Equation Millet -0.034 Maize 0.158 Sorghum -1.156 0.016 0.047 0.033 0.118 229 Table A4-5 (cont’d) Urban Coef. Std. Err. Compensated Price Elasticities Rice Rice -0.341 0.008 equation Millet 0.168 0.007 Maize 0.084 0.004 Sorghum 0.068 0.007 Millet Rice 0.563 0.034 Equation Millet -0.714 0.035 Maize 0.081 0.013 Sorghum 0.137 0.026 Maize Rice 0.446 0.051 Equation Millet 0.206 0.044 Maize -0.986 0.032 Sorghum 0.186 0.052 Sorghum Rice 0.627 0.090 Equation Millet 0.218 0.079 Maize 0.276 0.051 Sorghum -1.021 0.078 Source: Author. P>|z| Coef. Rural Std. Err. 0.000 -0.660 0.034 0.000 0.000 0.000 0.000 0.000 0.420 0.095 0.003 0.491 0.038 0.014 0.026 0.050 0.000 0.000 0.911 0.000 0.000 0.000 0.000 0.000 -0.723 0.109 0.291 0.609 0.048 0.020 0.040 0.071 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.116 -0.896 0.208 0.133 0.105 0.036 0.068 0.096 0.269 0.000 0.002 0.166 0.006 0.000 0.000 0.543 0.148 -0.819 0.103 0.039 0.078 0.000 0.000 0.000 230 P>|z| Table A4-6. Estimated Elasticities of the Censored QUAIDS Model for Cereals Demand by Urban Income Group—Total Cereals Expenditures Low-Income Middle-Income High-Income Coef. Std. Err. Coef. Std. Err. Coef. Std. Err. 0.124 0.416 0.037 0.174 0.880 1.079 1.070 1.454 0.012 0.027 0.029 0.043 1.239 0.415 1.032 1.247 0.050 0.125 0.288 0.198 0.072 0.088 0.102 0.030 0.144 0.342 0.190 0.161 0.059 0.068 0.068 0.077 0.088 -0.915 0.003 0.073 -0.012 -0.045 -1.035 -0.034 0.059 -0.060 0.009 -1.026 0.018 -0.274 0.009 0.006 0.020 0.007 0.028 0.027 0.028 0.037 0.022 0.027 0.047 0.028 0.041 -1.065 -0.122 -0.443 -0.027 0.023 -0.514 1.146 -0.123 0.258 0.208 -0.946 0.158 -0.286 0.054 0.052 0.123 0.065 0.137 0.162 0.281 0.210 0.163 0.197 0.338 0.257 0.260 0.174 0.085 0.122 0.077 -0.133 -0.948 0.050 0.025 0.054 -0.075 -0.098 -0.658 0.290 0.337 0.244 Expenditure Elasticities Rice 1.248 Millet 0.758 Maize 0.702 Sorghum 0.673 Uncompensated Price Elasticities Rice Equation Rice -0.997 Millet -0.157 Maize -0.108 Sorghum 0.000 Millet Equation Rice -0.196 Millet -0.243 Maize 0.066 Sorghum -0.259 Maize Equation Rice 0.071 Millet 0.002 Maize -0.996 Sorghum 0.130 Sorghum Rice 0.034 Equation Millet -0.265 Maize 0.242 Sorghum -1.014 231 Table A4-6. (cont’d) Low-Income Middle-Income High-Income Coef. Std. Err. Coef. Std. Err. Coef. Std. Err. 0.060 0.054 0.031 0.022 0.227 0.295 0.064 0.123 0.126 0.122 0.070 0.085 0.147 -0.318 0.146 0.096 0.067 0.674 -0.860 0.063 0.128 0.580 0.191 -0.945 0.111 0.437 0.005 0.004 0.007 0.004 0.026 0.027 0.014 0.025 0.042 0.050 0.048 0.034 0.079 -0.241 0.128 -0.097 0.089 0.305 -0.439 0.651 -0.034 1.299 0.570 -0.870 0.245 0.167 0.052 0.036 0.049 0.027 0.187 0.150 0.145 0.118 0.471 0.328 0.334 0.263 0.670 0.279 0.091 0.130 0.356 0.000 -0.828 0.077 0.019 0.056 0.089 -0.005 -0.557 0.497 0.321 0.248 Compensated Price Elasticities Rice Equation Rice -0.277 Millet 0.129 Maize 0.098 Sorghum 0.130 Millet Equation Rice 0.192 Millet -0.089 Maize 0.124 Sorghum -0.077 Maize Equation Rice 0.567 Millet 0.145 Maize -0.914 Sorghum 0.215 Sorghum Rice 0.460 Equation Millet -0.304 Maize 0.300 Sorghum -0.944 Source: Author. 232 Table A4-7. Estimated Elasticities of the Censored QUAIDS Model for Cereals Demand by Rural Income Group–Total Cereals Expenditures Low-Income Middle-Income High-Income Coef. Std. Err. Coef. Std. Err. Coef. Std. Err. 0.021 0.017 0.018 0.025 1.006 0.980 0.867 1.069 0.032 0.016 0.026 0.060 1.001 1.025 1.014 0.974 0.004 0.004 0.006 0.007 0.017 0.019 0.020 0.027 0.014 0.028 0.018 0.034 0.016 0.024 0.023 0.029 0.035 -0.973 -0.017 -0.006 0.000 -0.009 -0.963 0.003 0.011 0.014 0.042 -0.940 -0.088 -0.013 0.011 0.038 0.011 0.024 0.025 0.048 0.034 0.062 0.027 0.068 0.049 0.098 0.050 -0.991 -0.004 -0.004 0.003 -0.024 -0.993 0.006 -0.008 -0.017 0.010 -0.996 -0.004 0.020 0.003 0.004 0.003 0.003 0.005 0.005 0.005 0.004 0.007 0.009 0.007 0.007 0.005 0.056 0.025 0.068 -0.004 -0.072 -0.945 0.093 0.085 0.160 -0.011 -0.003 -0.988 0.006 0.005 0.006 Expenditure Elasticities Rice 0.654 Millet 1.248 Maize 1.030 Sorghum 1.054 Uncompensated Price Elasticities Rice Equation Rice -0.781 Millet 0.035 Maize -0.046 Sorghum 0.052 Millet Equation Rice -0.145 Millet -1.010 Maize 0.060 Sorghum -0.051 Maize Equation Rice 0.009 Millet 0.039 Maize -1.041 Sorghum -0.053 Sorghum Rice 0.035 Equation Millet -0.091 Maize -0.039 Sorghum -0.894 233 Table A4-7. (cont’d) Low-Income Middle-Income High-Income Coef. Std. Err. Coef. Std. Err. Coef. Std. Err. 0.013 0.020 0.012 0.018 0.015 0.028 0.013 0.025 0.025 0.037 0.022 0.034 0.047 -0.607 0.335 0.119 0.167 0.347 -0.622 0.122 0.171 0.338 0.363 -0.834 0.048 0.369 0.015 0.025 0.007 0.019 0.029 0.046 0.024 0.047 0.041 0.100 0.050 0.105 0.059 -0.516 0.286 0.096 0.141 0.457 -0.696 0.104 0.136 0.451 0.308 -0.897 0.136 0.495 0.003 0.003 0.002 0.002 0.006 0.005 0.003 0.003 0.012 0.013 0.007 0.008 0.008 0.078 0.023 0.067 0.367 0.064 -0.768 0.134 0.083 0.155 0.266 0.092 -0.853 0.008 0.005 0.006 Compensated Price Elasticities Rice Equation Rice -0.585 Millet 0.291 Maize 0.058 Sorghum 0.148 Millet Equation Rice 0.215 Millet -0.513 Maize 0.202 Sorghum 0.176 Maize Equation Rice 0.326 Millet 0.469 Maize -0.907 Sorghum 0.117 Sorghum Rice 0.369 Equation Millet 0.298 Maize 0.103 Sorghum -0.713 Source: Author. 234 Table A4-8. Estimated Parameters of the Censored QUAIDS Model for Cereals Demand by Place of Residence–Only Purchased Cereals Expenditure Coef. Urban Std. Err. P>|z| Coef. Rural Std. Err. P>|z| Constants α1 1.230 0.133 0.000 -0.579 0.157 0.000 α2 0.854 0.244 0.000 -0.042 0.100 0.673 α3 1.200 0.234 0.000 -0.018 0.253 0.944 α4 -3.465 0.436 0.000 1.506 0.218 0.000 Expenditure β1 -0.139 0.020 0.000 0.102 0.011 0.000 β2 -0.112 0.043 0.010 0.029 0.014 0.038 β3 -0.210 0.035 0.000 -0.062 0.029 0.030 β4 0.514 0.071 0.000 -0.232 0.028 0.000 Prices γ11 -0.122 0.036 0.001 -0.029 0.017 0.088 γ12 -0.065 0.052 0.216 -0.034 0.008 0.000 γ13 -0.189 0.033 0.000 -0.025 0.018 0.176 γ14 0.477 0.099 0.000 0.152 0.029 0.000 γ22 -0.146 0.071 0.039 0.033 0.011 0.002 γ23 -0.183 0.084 0.029 0.003 0.018 0.884 γ24 0.336 0.219 0.126 -0.005 0.025 0.837 γ33 -0.252 0.101 0.013 -0.004 0.035 0.920 γ34 0.747 0.243 0.002 0.017 0.040 0.670 γ44 -2.121 0.590 0.000 -0.225 0.066 0.001 Expenditure Squared λ1 0.006 0.001 0.000 -0.001 0.000 0.000 λ2 0.007 0.002 0.000 0.001 0.000 0.140 λ3 0.008 0.001 0.000 0.005 0.001 0.000 λ4 -0.017 0.003 0.000 0.004 0.001 0.000 PDFs Rice 0.001 0.003 0.627 0.000 0.001 0.652 Millet 0.000 0.003 0.983 0.000 0.001 0.504 Maize 0.001 0.004 0.858 -0.001 0.002 0.751 Sorghum -0.002 0.007 0.780 -0.002 0.001 0.021 Rice=1, millet=2, maize= 3 and sorghum=4. γ23= Equation i and commodity j. The regional dummy excluded in the estimation was Ségou (the reference region) 235 Table A4-8. (cont’d) Coef. Urban Std. Err. P>|z| Coef. Rural Std. Err. P>|z| HH Adult Equivalent Rice 0.007 0.000 0.000 -0.012 0.002 0.000 Millet -0.010 0.001 0.000 -0.006 0.001 0.000 Maize 0.005 0.003 0.073 0.007 0.004 0.109 Sorghum -0.015 0.002 0.000 0.011 0.002 0.000 Regional Dummies Kayes Rice 0.014 0.012 0.232 0.791 0.083 0.000 Millet -0.074 0.020 0.000 -0.422 0.059 0.000 Maize 0.063 0.060 0.297 -0.165 0.093 0.077 Sorghum 0.338 0.043 0.000 0.019 0.049 0.694 Koulikoro Rice -0.025 0.018 0.177 0.566 0.067 0.000 Millet -0.160 0.027 0.000 -0.121 0.031 0.000 Maize 0.013 0.069 0.853 -0.250 0.073 0.001 Sorghum 0.785 0.067 0.000 -0.070 0.029 0.017 Sikasso Rice -0.169 0.033 0.000 0.656 0.077 0.000 Millet -0.183 0.047 0.000 -0.820 0.092 0.000 Maize 0.184 0.127 0.147 0.414 0.113 0.000 Sorghum 0.184 0.056 0.001 0.233 0.074 0.002 Mopti Rice -0.042 0.013 0.001 0.190 0.025 0.000 Millet 0.074 0.020 0.000 0.184 0.012 0.000 Maize -0.089 0.037 0.016 -0.500 0.059 0.000 Sorghum 0.014 0.015 0.319 -0.022 0.042 0.603 Tombouctou Rice 0.057 0.018 0.002 -0.199 0.030 0.000 Millet 0.002 0.020 0.919 0.107 0.017 0.000 Maize -0.041 0.167 0.808 -0.115 0.048 0.017 Sorghum -0.657 0.074 0.000 0.133 0.059 0.023 Rice=1, millet=2, maize= 3 and sorghum=4. γ23= Equation i and commodity j. The regional dummy excluded in the estimation was Ségou (the reference region) 236 Table A4-8. (cont’d) Urban Rural Gao Rice -0.008 0.019 0.667 -0.465 0.089 0.000 Millet 0.028 0.028 0.317 0.038 0.054 0.479 Maize -0.089 0.191 0.641 0.136 0.097 0.160 Sorghum -0.010 0.033 0.752 -0.044 0.044 0.320 Bamako Rice -0.027 0.011 0.013 Millet -0.063 0.017 0.000 Maize 0.016 0.060 0.787 Sorghum 0.504 0.049 0.000 tau Rice 0.848 0.086 0.000 3.226 0.199 0.000 Millet 0.292 0.025 0.000 0.065 0.041 0.114 Maize -0.036 0.126 0.775 0.195 0.145 0.178 Sorghum 1.496 0.131 0.000 -0.256 0.072 0.000 Rice=1, millet=2, maize= 3 and sorghum=4. γ23= Equation i and commodity j. The regional dummy excluded in the estimation was Ségou (the reference region) tau - are the residuals from the reduced form regression of total cereal expenditure on the set of instruments and explanatory variables 237 Table A4-9. Estimated Elasticities of the Censored QUAIDS Model for Cereals Demand by Place of Residence—Only Purchased Cereals Expenditures Urban Coef. Std. Err. P>|z| Coef. Rural Std. Err. P>|z| Expenditure Elasticities Rice 0.874 Millet 0.826 Maize 0.393 Sorghum 2.817 Uncompensated Elasticities Rice Rice equation -0.898 Millet 0.032 Maize 0.047 Sorghum -0.314 Millet Rice Equation 0.208 Millet -1.286 Maize -0.110 Sorghum -0.373 Maize Rice Equation -0.171 Millet -0.442 Maize -1.271 Sorghum 0.903 Sorghum rice Equation 0.462 Millet 0.691 Maize 1.406 Sorghum -4.658 0.017 0.108 0.113 0.228 0.000 0.000 0.001 0.000 1.141 1.060 0.893 0.401 0.018 0.024 0.087 0.074 0.000 0.000 0.000 0.000 0.016 0.018 0.042 0.055 0.000 0.086 0.261 0.000 -1.004 -0.041 -0.030 0.058 0.010 0.012 0.015 0.021 0.000 0.001 0.045 0.006 0.057 0.097 0.094 0.081 0.000 0.000 0.239 0.000 -0.056 -0.937 0.009 -0.046 0.014 0.019 0.025 0.034 0.000 0.000 0.738 0.179 0.079 0.177 0.180 0.451 0.030 0.012 0.000 0.045 -0.123 -0.001 -0.995 0.153 0.062 0.065 0.126 0.133 0.049 0.989 0.000 0.250 0.211 0.498 0.481 1.184 0.028 0.165 0.003 0.000 0.378 -0.037 0.054 -1.389 0.062 0.063 0.070 0.129 0.000 0.557 0.441 0.000 238 Table A4-9. (cont’d) Urban Coef. Std. Err. Compensated Price Elasticities Rice Rice equation -0.307 0.011 Millet 0.176 0.014 Maize 0.078 0.014 Sorghum -0.058 0.023 Millet Rice Equation 0.858 0.113 Millet -1.140 0.107 Maize 0.005 0.047 Sorghum -0.150 0.045 Maize Rice Equation -0.241 0.269 Millet -0.841 0.378 Maize -1.243 0.185 Sorghum 1.089 0.522 Sorghum Rice Equation 3.073 0.609 Millet 1.709 0.910 Maize 1.399 0.422 Sorghum -4.443 1.169 Source: Author. P>|z| Coef. Rural Std. Err. P>|z| 0.000 0.000 0.000 0.011 -0.344 0.302 0.043 0.126 0.012 0.008 0.003 0.007 0.000 0.000 0.000 0.000 0.000 0.000 0.907 0.001 0.518 -0.634 0.047 0.075 0.021 0.018 0.007 0.020 0.000 0.000 0.000 0.000 0.370 0.026 0.000 0.037 -0.211 0.252 -0.957 0.370 0.341 0.213 0.126 0.255 0.535 0.238 0.000 0.146 0.000 0.060 0.001 0.000 1.425 0.045 0.045 -1.352 0.176 0.114 0.035 0.135 0.000 0.691 0.197 0.000 239 Table A4-10. Estimated Elasticities of the Censored QUAIDS Model for Cereals Demand by Urban Income Group—Only Purchased Cereals Expenditures Low-Income Middle-Income High-Income Coef. Coef. Coef. Expenditure Elasticities Rice 0.991 Millet 1.239 Maize 1.003 Sorghum 1.901 Uncompensated Price Elasticities Rice Equation Rice -0.928 Millet 0.034 Maize -0.023 Sorghum -0.069 Millet Equation Rice -0.051 Millet -1.221 Maize -0.013 Sorghum 0.212 Maize Equation Rice -0.055 Millet -0.071 Maize -0.967 Sorghum 0.050 Sorghum Rice -0.438 Equation Millet 0.053 Maize 0.161 Sorghum -2.013 Std. Err. Std. Err. Std. Err. 0.006 0.132 0.088 0.229 1.096 1.203 0.643 -0.151 0.017 0.050 0.073 0.231 1.075 0.905 1.716 0.719 0.014 0.035 0.210 0.091 0.018 0.013 0.010 0.021 0.078 0.069 0.046 0.083 0.031 0.051 0.051 0.093 0.101 -1.281 0.330 0.264 -0.260 0.773 -1.719 -0.854 0.623 0.341 -1.410 -0.455 0.502 -0.128 0.102 0.112 0.126 0.111 0.331 0.323 0.347 0.356 0.312 0.465 0.385 0.399 0.322 -1.079 0.017 -0.048 0.084 0.156 -1.029 0.414 -0.269 0.438 0.202 -0.926 -0.482 0.180 0.019 0.014 0.035 0.021 0.044 0.030 0.078 0.056 0.071 0.082 0.368 0.188 0.071 0.127 0.094 0.396 0.931 -0.750 -1.967 0.529 0.381 0.689 -0.229 -0.334 -0.777 0.054 0.136 0.120 240 Table A4-10. (cont’d) Low-Income Middle-Income High-Income Coef. Coef. Coef. Uncompensated Price Elasticities Rice Equation Rice -0.261 Millet 0.200 Maize 0.066 Sorghum 0.050 Millet Equation Rice 0.754 Millet -0.998 Maize 0.084 Sorghum 0.202 Maize Equation Rice 0.486 Millet 0.025 Maize -0.894 Sorghum 0.132 Sorghum Rice -0.034 Equation Millet 0.444 Maize 0.278 Sorghum -1.873 Source: Author. Std. Err. Std. Err. Std. Err. 0.016 0.009 0.003 0.007 0.055 0.059 0.028 0.042 0.085 0.102 0.052 0.102 0.201 -0.535 0.427 0.174 -0.037 1.879 -1.514 -0.334 0.494 1.387 -2.754 -0.409 0.706 -0.376 0.105 0.081 0.045 0.052 0.453 0.323 0.172 0.229 0.873 0.945 0.384 0.521 0.816 -0.354 0.205 0.055 0.118 0.820 -0.867 0.286 -0.077 2.244 0.681 -0.808 -0.354 0.926 0.016 0.010 0.013 0.009 0.048 0.031 0.041 0.032 0.206 0.142 0.382 0.181 0.154 0.269 0.088 0.379 1.421 -0.585 -1.979 0.789 0.299 0.702 -0.290 -0.280 -0.721 0.108 0.137 0.115 241 Table A4-11. Estimated Elasticities of the Censored QUAIDS Model for Cereals Demand by Rural Income Group—Only Purchased Cereals Expenditures Low-Income Middle-Income High-Income Coef. Coef. Coef. Expenditure Elasticities Rice 0.994 Millet 0.955 Maize 1.071 Sorghum 1.108 Uncompensated Price Elasticities Rice Equation Rice -1.002 Millet -0.005 Maize 0.002 Sorghum 0.002 Millet Equation Rice 0.012 Millet -1.004 Maize -0.010 Sorghum 0.017 Maize Equation Rice -0.004 Millet -0.013 Maize -0.985 Sorghum 0.009 Sorghum Rice -0.016 Equation Millet 0.030 Maize 0.009 Sorghum -1.057 Std. Err. Std. Err. Std. Err. 0.001 0.010 0.015 0.032 1.054 1.199 0.095 0.777 0.032 0.073 0.418 0.369 0.919 1.015 2.151 2.462 0.026 0.209 0.316 0.489 0.002 0.002 0.001 0.002 0.003 0.006 0.008 0.008 0.001 0.014 0.014 0.021 0.005 -0.926 -0.095 -0.117 0.197 -0.143 -1.008 0.217 -0.078 -0.180 0.462 -1.635 0.059 0.398 0.035 0.061 0.058 0.096 0.061 0.082 0.154 0.159 0.110 0.460 0.708 0.247 0.168 -0.963 0.217 -0.295 0.161 0.309 -1.535 0.116 -0.117 -0.614 0.236 -2.713 -1.254 0.391 0.115 0.105 0.147 0.188 0.123 0.206 0.290 0.364 0.415 0.820 1.368 0.718 0.460 0.014 0.020 0.025 -0.110 0.029 -1.310 0.316 0.200 0.315 -0.177 -0.359 -2.459 0.577 0.549 0.732 242 Table A4-11. (cont’d) Low-Income Middle-Income High-Income Coef. Coef. Coef. Uncompensated Price Elasticities Rice Equation Rice -0.429 Millet 0.274 Maize 0.052 Sorghum 0.092 Millet Equation Rice 0.575 Millet -0.738 Maize 0.047 Sorghum 0.097 Maize Equation Rice 0.581 Millet 0.244 Maize -0.929 Sorghum 0.116 Sorghum Rice 0.572 Equation Millet 0.371 Maize 0.062 Sorghum -0.955 Source: Author. Std. Err. Std. Err. Std. Err. 0.002 0.001 0.000 0.000 0.003 0.007 0.002 0.003 0.012 0.061 0.014 0.040 0.010 -0.324 0.258 0.020 0.159 0.438 -0.652 0.103 0.073 -1.089 1.731 -1.631 0.121 1.765 0.038 0.036 0.009 0.030 0.095 0.085 0.042 0.084 0.714 1.598 0.720 0.473 0.533 -0.425 0.403 -0.025 0.148 1.055 -1.251 0.079 0.028 -1.621 1.343 -2.624 -2.070 2.450 0.107 0.074 0.031 0.073 0.260 0.192 0.091 0.219 1.916 2.562 1.364 1.302 1.246 0.036 0.010 0.023 0.020 0.044 -1.236 0.532 0.113 0.345 0.384 -0.096 -2.228 0.978 0.294 0.712 243 CHAPTER 5. WELFARE EFFECTS OF CEREAL PRICE SHOCKS IN MALI 5.1. Problem Statement Rice, millet, maize and sorghum are primary staple foods in Mali. Increases in cereals prices are likely to have substantial negative impacts on the poor (see Ivanic and Martin, 2008; Joseph and Wodon, 2008; Wodon and Zaman, 2010). Limited empirical evidence on aggregate as well as micro-level demand parameters differentiated by important household characteristics (e.g., household place of residence) in Mali places a limit on policy makers’ ability to make informed food policy decisions. If policymakers are to intervene to help those most adversely impacted by food price changes, then policymakers need to identify those who have been most harmed and the magnitude of that harm (Friedman and Levinsohn, 2002). Effective design of targeted actions therefore requires knowledge of the distribution of the effects of changes in income as well as other factors that determine food demand across different segments of the population. 5.2. Research Objectives The goal of this chapter is to estimate the welfare effects of cereals price shocks, allowing for second-order demand responses (substitution in demand) to cereal price changes. The study is focused on the relative differences in the welfare effect of cereals price shocks across income distribution and place of residence, with the goal to determine households that are most likely affected by cereals price changes. Specifically, the analysis seeks to:  Link observed cereals price changes to changes in household welfare using the household cereals demand parameters estimated in chapter 4 (that take into account differences in household socio-economic and demographic characteristics, geographic location, and place of residence) to compute a welfare measure for a cereal price change. The welfare 244 measure used in this study is a proportional compensating variation (CV) adapted from de Janvry, et al. (2008) and that allows for substitutions in consumption.  Distinguish the welfare effects of cereals price changes by place of residence and household per capita expenditure group. 5.3. Literature Review A vast literature exists on the welfare implications of food price increases. The welfare effects of changes in food prices on households can be traced through three principal channels: by affecting the affordability of an important component of the consumption basket; by affecting the returns from farming, insofar as the household is directly engaged in this activity; and by affecting the demand for labor in agriculture and thus the wage income of household members who work for agricultural producers (Aksoy and Hoekman, 2010). A fourth pathway is described in Lele and Mellor (1972) and includes the effect of food prices on real wages and hence the impact on the demand for labor in non-agricultural activities. Deaton (1989) observed that, as many households in developing countries are both producers and consumers, the net impact of price changes is determined by which effect is greater: whether the household is a net consumer/buyer or a net producer/seller. There has been a general consensus in the literature that first-order approximations which focus only on the direct effects on consumption of a good resulting from a change in its price may not be enough in evaluating the welfare consequences of food price changes. For instance Mghenyi et al. (2011) argue that first-order approximation approaches may be restrictive for evaluating the welfare effect of a large discrete price change because supply and demand responses to a major price change may be substantial. When the price of a food item increases, 245 consumers can switch to cheaper/more affordable items or producers can respond to the increase by expanding supply or reallocating inputs to capture the increase in price. While most urban households rely on the market for almost all of their food needs, most rural households, in contrast, are both food producers and consumers. Thus, in urban areas while changes in food prices directly affect the affordability of the food for which the price has increased, in the rural areas a food price increase hurts them as consumers on one hand, but on the other hand, it has the potential of raising the incomes of food-producing households and even that of non-food producing households through multiplier effects. Ideally, one would need to account for second-order effects that examine not only substitution effects in consumption but also the effects on production of food price increases, as well as the dynamic aspect (multiplier effects— e.g., wage effects) of the food price changes (Nouve and Wodon,2008; Porto, 2005;and Porto, 2010). Notwithstanding, the specific approach used in examining the welfare impacts of food price changes has been influenced by data availability and whether the interest is in measuring short, medium or long-term effects; or static as opposed to dynamic effects. Using household budget survey data for Mali, Joseph and Wodon (2008) provide an assessment of the short-term impact on poverty of the increase in the price of cereals. Specifically, they examine, using statistical analysis and non-parametric methods, both the impact on food producers (who benefit from an increase in prices) and food consumers (who lose out when the price increases), with a focus on poor producers and consumers. They provide estimates of the impact on poverty of higher food prices based on a number of assumptions. First, they assume that the cost of an increase in food prices for a household translates into an equivalent reduction of its consumption in real terms–they do not take into account the price elasticity of demand which may lead to 246 substitution effects and thereby help offset part of the negative effect of higher prices for certain food items. Second, they assume an increase for producers in the value of their net sales of food translates into an increase of their consumption of equivalent size. Third, they assume that changes in prices do not affect households when food is home-produced and consumed. To assess impacts, they compare poverty measures obtained after the increase in prices to baseline poverty measures. This implicitly means that they do not take into account the potential spillover effects of the increase in food prices for the food items included in the analysis on the prices for items not included. Nouve and Wodon (2008) took a step further in the work done by Joseph and Wodon (2008) and in a dynamic general equilibrium framework estimate the broader medium-term impact of higher rice prices in Mali on poverty. They compare a base scenario (business as usual) to six different scenarios that combine rice price changes and policy responses (import tax cuts on rice and measures to increase productivity of domestic rice production). They find that considering either an 80%40 or a 110%41 increase in international rice prices from the level in 2006, a 15%42 an increase in productivity will have a larger impact than a 100% reduction in taxes. The current study uses the same household survey data as Joseph and Wodon. However, unlike Joseph and Wodon (2008), the study considers own-price and cross-price demand effects in examining the welfare effects of cereals price changes. The data set covers 1566 urban households and 2888 rural households in Mali taken from the 2006 ELIM, as described in Chapter 4. The presence of rural households (the majority of whom are food producers and This is the level of the increase actually observed in CFAF in 2008. This is the level of the increase in US dollar terms. 42 An arbitrary level of productivity gains chosen for illustrative purposes. 247 40 41 consumers) warrants taking into consideration the effects of cereal price increases on cereals demand and supply. The estimation of household supply response to food price changes, however, requires detailed production information (e.g., production quantities/value and shares by crop and by household, supply elasticities, etc.) which are not available in the ELIM-2006 data file. While it would be appropriate to estimate the overall welfare changes (i.e., including producer welfare), due to data limitations on the supply side, welfare estimation in this chapter is limited only to the consumption response (direct and substitution effects). Producer supply response and wage effects are not taken into consideration. Consequently, the estimated impact is considered the upper-limit of the effect of cereal price shocks on welfare. 5.4. Methodological Approach and Data To evaluate the partial equilibrium welfare effect of cereals price changes from an initial price level, the analysis measures a proportional compensating variation of a price change which takes into account demand responses to a change in price. The formula for the second-order approximation is adapted from de Janvry and Sadoulet (2008) and also used by Friedman and Levinsohn (2002). Starting from a household’s indirect utility function, which reflects the household’s consumption components, a second-order Taylor expansion to the indirect utility function is used to derive a welfare measure that accounts for demand responses. The idea is that using a set of reference prices, we can compute how well-off or worse-off households are as a result of the price changes, moving from their initial utility level to the new utility level in response to the changes in cereals prices. The CV is the difference between the minimum expenditure required to achieve the original utility level (2006) at the new prices, and the initial total expenditure–i.e., the amount of money the household would need to be given at the new set 248 of (higher) prices in order to attain the initial level of utility (2006). Approximated using a second-order Taylor expansion of the minimum expenditure function, the CV is written as: 𝐶𝑉 ≈ 𝑑 (𝑑𝑙𝑛𝑝𝑖 )(𝑑𝑙𝑛𝑝𝑗 )] ∑ 𝑤𝑖𝑑 𝑑𝑙𝑛𝑝𝑖 + 0.5 [∑ ∑ 𝑤𝑖𝑑 𝑒𝑖𝑗 𝑖=1 (5 − 1) 𝑖=1 𝑗=1 𝑑 Estimates of the compensated own (𝑒𝑖𝑖𝑑 ) and cross-price elasticities (𝑒𝑖𝑗 ) of demand for rice, maize, millet and sorghum by place of residence and income group are all available from chapter 4. The share of each cereal type in the household’s food budget in the initial period – 2006 (𝑤𝑖𝑑 ) is directly calculated from the survey data. 𝑑𝑙𝑛𝑝𝑖 approximates the proportionate change in the price of commodity i. The first-order effect is captured by the first term in equation 5-1, and it implicitly assumes zero demand elasticities (i.e., household consumption behavior remains unaltered with price changes). The second-order effect depends on the compensated price elasticities. From equation 5-1 it is clear that the second-order effects depend on the magnitude of the price change as well as the relative importance of the product in purchases in the household’s budget. Ideally, household-specific estimates are required for the computation of household specific proportional welfare effects from price changes. To account for consumption responses, we estimate first and second-order impacts using the budget shares and the compensated demand elasticities. 249 Table 5-1. Average Consumer Price Changes Compared to 2006 (%) Period Rice Millet Maize Sorghum 2008 21 9 17 10 2009 21 21 28 21 2010 16 15 20 14 2011 23 19 30 23 Source: Author’s computation using price data from OMA-Mali. Average 14 23 16 24 The welfare measure is computed jointly for rice, millet, sorghum and maize because these are the cereals for which average consumption is highest. The welfare measure is computed by comparing cereals prices observed in 2006 (the year in which the HBS was collected-reference prices) to prices observed in each of the years 2008, 2009, 2010 and 201143. Price data at the administrative unit level for 2006 to 2011 were obtained from Mali’s Observatoire du Marche Agricole (OMA). Given the constructed nature of the observed price changes, variations in prices within a given year are mainly due to differences in geographic region. However, the year-to-year variations in prices are due to factors other than geographic location–e.g., supply conditions. Price changes were computed at the district or “cercle” as the natural logarithm of the ratio of the price in year t+1 to the price in year t, i.e., dlnPi= ln(pit+1/Pit). Table 5-1 summarizes the average price changes for all locations covered by ELIM-2006. Average price rose rapidly for all cereals over time but maize price changes were more dramatic compared to the other cereals. The estimated increase in the price of rice in 2008 is in line with Nouve and Wodon’s estimate of an increase in the average price of rice (covers both imported and locally produced rice) of 21 percent in 2008 against the base scenario (2006). Comparing 2007 to 2006, price changes were 0% for rice, -11% for millet, -7% for maize and 5% for sorghum. 250 43 5.5. Findings The welfare effects of cereal price changes observed from 2008 to 2011 were estimated by place of residence and per capita income group to illustrate variations across different segments of the population. Table 5-2 presents the welfare measure as a share of total household cereals expenditure in 2006 by place of residence. The table reports both the first-order and the full effect (first plus second-order effects) considering all four cereals (rice, millet, sorghum and maize) and the substitution responses among them. Table 5-2. Compensating Variation of Cereals Price Changes by Place of Residence (% of Total Cereals Expenditures) Urban 2008 2009 2010 2011 Source: Author. First-order 18.0 22.2 16.7 23.0 Rural Full Effect 17.7 22.0 16.6 22.8 First-order 15.8 22.9 16.5 23.7 Full Effect 15.5 22.7 16.2 23.4 The figures reported in Table 5-2 illustrate that the first-order approximation of the impact of price changes which implicitly assumes that households are unable to change their consumption patterns when prices change (equivalent to assuming that all elasticities are zero), captures almost all of the impact of price changes on welfare. It has been argued that ignoring consumption responses (substitution effects in consumption) in welfare analysis (the secondorder approximation) may lead to significant biases and inappropriate inferences (Friedman and Levinsohn, 2002). However, as seen from the table above, there is not much difference between the first-order and the fuller impacts of cereals price changes considering the urban and rural sub-samples. This reflects the fact that during this period all cereals prices were rising sharply, limiting the scope for substitution to “cheaper” cereals. Across all the years, the first-order 251 impact was larger than the full impact by less than 1%. Thus, consistent with a priori expectations, the first-order effect overstates, albeit marginally, the welfare losses for urban and rural households. Furthermore, on examining differences in the full effect between the rural and the urban sample, we notice that in 2008 and 2010, the full effect was higher in the urban than the rural areas, while in 2009 and 2011 the rural full effects were larger than the urban full effects. Looking at Table 5-2, we observe that the changes vary year to year and track remarkably the unweighted average of price changes of all cereals from year to year as reported in Table 5-1. Although the figures displayed in Table 5-2 do not reveal much difference between the urban and the rural population in the percentage compensation based on total household cereals expenditures in 2006, the actual magnitude of the welfare losses from cereals price changes by place of residence are quite substantial and different by place of residence. As seen from Table 4-13, average annual expenditure on cereals per household in 2006 is 320,306 CFAF (593 US $) in the urban area and 313,797 CFAF (581 US $) in the rural area. Also, as revealed by the data, average annual total consumption expenditure (proxy for income) is 3,039,927 CFAF (5,624 US $) per household in the urban area and 1,328,788 CFAF (2,458 US $) in the rural area. Thus, cereals account for an average of 10.5% of urban and 23.6% of rural total household consumption expenditures. Based on these figures, the actual magnitude of the welfare loss from cereals price changes (effect on total cereals expenditure and effect on total household consumption expenditure) are computed and reported in Table 5-3. In 2008 for instance, considering the full welfare impact, on average urban households had to be compensated by 17.7% (56,719 CFAF=105 US $) while rural households had to be compensated by 15.5% (48,697 CFAF = 90 US $) of their total cereals expenditures in 2006. This is equivalent to saying 252 that the observed price changes in 2008 would result in a compensation of urban households of about 1.9% and rural households of about 3.7% of their 2006 total household consumption expenditures (proxy for income). The figures in Table 5-3, therefore, show the adverse effect of the higher prices on Malian population–essentially, everyone got approximately a 2-6% income reduction because of the higher cereals prices. The welfare loss from higher cereals prices was greater in the rural area than the urban area without considering the possibility of producer supply response in the rural areas. However, because many other prices (e.g., of other foods and of energy) also increased sharply during this period, the impact of what became known in Mali as the “crisis of the high cost of living” was greater than that indicated by just the cereal price increases. Table 5-3. Magnitude of Welfare Loss Implied by Cereals Price Changes by Place of Residence Urban Value of compensation based on 2006 average cereals expenditure (CFAF) Rural Year CV Percent of CV Value of Percent of (Full average total (Full compensation average total impact) household impact) based on household in % consumption in % 2006 average consumption expenditure cereals expenditure in 2006 expenditure in 2006 (CFAF) 2008 56,719 48,697 17.7 (105) 1.9% 15.5 (90) 3.7% 2009 22.0 70,506 71,132 (131) 2.3% 22.7 (132) 5.4% 2010 16.6 53,037 50,798 (98) 1.7% 16.2 (94) 3.8% 2011 22.8 72,999 73,523 (135) 2.4% 23.4 (136) 5.5% Source: Author. Note: The figures in parenthesis are US dollar equivalents. Table 5-4 shows first-order and the full effect by place of residence and per capita income group considering all cereals and substitution amongst them. The welfare measure of 253 cereals price changes (in a similar manner to the expenditure shares shown in Table 4-19) do not show much difference across per capita income groups within a given place of residence in terms of percentage in total cereals expenditures in 2006. However, in absolute terms the impacts differ widely. Table 5-4. Compensating Variation of Cereals Price Changes by Place of Residence and Income Group (% of Total Cereals Expenditures) Urban First-order 2008 2009 2010 2011 18.1 22.8 16.3 22.9 2008 2009 2010 2011 18.2 22.0 16.8 23.1 2008 17.8 2009 21.7 2010 17.0 2011 23.2 Source: Author’s computation. Rural Full Effect First-order Low-Income Group 17.8 15.2 22.6 23.6 16.2 16.8 22.7 23.5 Middle-Income Group 18.0 15.7 21.9 23.0 16.7 16.6 22.8 24.0 High-Income Group 17.5 16.5 21.8 22.0 17.0 16.0 23.1 23.7 Full Effect 15.0 23.4 16.7 23.3 15.4 22.7 16.3 23.6 16.2 21.7 15.6 23.3 Based on the average annual household total consumption expenditures (proxy for income) by place of residence and per capita income group as shown in Table 4-7, and the average annual household expenditures on cereals by place of residence and income group as shown in Table 413, the estimated welfare losses from higher cereals prices by place of residence and income group are as shown in Table 5-5. In the urban population, the absolute values of the welfare losses based on average expenditures on cereals in 2006 increases from the low- to the middle-income group but declines 254 from the middle- to the high-income group. However, the percentage of household income of the welfare loss is lowest for the high-income group and largest for the low-income group. In 2008 for instance, urban low-income households had to be compensated by about 3.7% of their average 2006 total household consumption expenditures; urban middle-income households had to be compensated by about 2.5% of their average 2006 total household consumption expenditures; while urban high-income households had to be compensated by about 1.0% of their average 2006 total household consumption expenditures (Table 5-5). In the rural population, the absolute value of the welfare loss based on average household cereals expenditures in 2006 increased from the low- to the high-income households. However, like in the urban group, the loss in percentage terms based on total household expenditures generally declined from the low- to the high-income group. In 2009 for instance, the percentage compensation based on average total household consumption expenditures in 2006 was 6.5% for rural low-income households; 6.3% for rural middle-income households, and 4.2% for the rural high-income households. Thus, in both the rural and the urban locations, the welfare loss from observed price changes in the period 2008 to 2011 (as a proportion to total household consumption expenditures) was greater for poorer households than richer households. Also, one might argue that the capacity of a poor family to absorb an X% reduction in income is lower than that of a rich household. 255 Table 5-5. Magnitude of Welfare Loss Implied by Cereals Price Changes by Place of Residence and per Capita Income Group Year CV (Full impact) in % 2008 17.8 2009 22.6 2010 16.2 2011 22.7 2008 18.0 2009 21.9 2010 16.7 2011 22.8 2008 17.5 2009 21.8 2010 17.0 2011 23.1 Urban Value of Percent of CV (Full compensation average total impact) based on household in % 2006 average consumption cereals expenditure expenditure in 2006 (CFAF) Low-Income 51,000 3.7% 15.0 (95) 64,753 4.7% 23.4 (120) 46,416 3.4% 16.7 (86) 65,040 4.7% 23.3 (121) Middle- Income 66,280 2.5% 15.4 (123) 80,640 3.1% 22.7 (150) 61,493 2.3% 16.3 (114) 83,954 3.2% 23.6 (156) High-Income 53,583 1.0% 16.2 (99) 66,749 1.3% 21.7 (124) 52,052 1.0% 15.6 (97) 70,729 1.4% 23.3 (125) Source: Author. Note: The figures in parenthesis are US dollar equivalents. 256 Rural Value of Percent of compensation average total based on 2006 household average consumption cereals expenditure expenditure in 2006 (CFAF) Low-Income 33,293 4.1% ( 62) 51,937 6.5% (96) 37,066 4.6% (69) 51,715 6.4% (96) Middle- Income 52,646 4.3% (98) 77,602 6.3% (144) 55,723 4.5% (103) 80,678 6.5% (150) High-Income 61,179 3.1% (114) 81,949 (152) 4.2% 58,913 (109) 87,992 (163) 3.0% 4.5% To check the validity of the estimated welfare impact by income group and place of residence, given that: a) rice is the most important share in the cereals budget for both the rural and urban households; and also b) that the largest difference in budget share between the rural and the urban place of residence are noticeable in the case of rice, the full effect of rice price changes were also computed (i.e., taking into account the share of rice and the response of rice and the other cereals to changes in rice prices). Table 5-6 reports the first-order or immediate response to changes in rice prices as well as the full effect of rice price changes, by place of residence. Table 5-6. Compensating Variation Implied by Rice Price Changes by Place of Residence (%) Urban First-order 2008 13.8 2009 14.1 2010 11.0 2011 15.3 Source: Author’s calculations. Rural Full-Effect 13.5 13.9 10.8 15.2 First-order 7.2 7.1 5.0 8.0 Full Effect 6.8 6.8 4.9 7.7 As shown in Table 5-6, urban and rural households suffered welfare losses from higher rice prices in the period 2008-2011. The first-order effect marginally overstates the welfare losses for urban households. The results reveal some heterogeneity in the impact of higher rice prices by place of residence. In terms of percentage compensation based on average expenditures on cereals in 2006, the burden of higher rice prices fell more on urban households than rural households. On average, urban (rural) households require a compensation of about 13.5% (6.8%) in 2008, 13.9% (6.8%) in 2009, 10.8% (4.9%) in 2010 and 15.2% (7.7%) in 2011 of their 2006 cereals budget for the higher rice prices they faced in 2008, 2009, 2010 and 2011 respectively. Thus, the results indicate that the relative impact of higher rice prices is more adverse for urban 257 households than for rural households. This is not surprising because of the much larger share of rice in the urban food budget. Examining the magnitude of the welfare loss by place of residence, we observe that the actual value of the compensation required to bring the households to their 2006 cereals expenditure level is higher in absolute terms for urban households than rural households (Table 5-7). However, because average total household consumption expenditures and average total household cereals expenditures in 2006 are much higher for urban households than rural households, the percentage of the compensation based on the average total household consumption expenditures in 2006 is slightly lower for the urban than for rural areas. Hence, although the actual amount of the compensation is higher for urban households than rural households, the percentage reduction in total household expenditure (proxy for income) is greater for rural households than urban households. Table 5-7. Magnitude of Welfare Loss Implied by Rice Price Changes by Place of Residence Year CV (Full impact) in % 2008 13.5 2009 13.9 2010 10.8 2011 15.2 Urban Value of compensation based on 2006 average cereals expenditure (CFAF) 43,242 (80) 44,523 (83) 34,593 (64) 48,687 (90) Percent of average total household consumption expenditure in 2006 1.4% 1.5% 1.1% 1.6% Rural CV Value of Percent of (Full compensation average total impact) based on household in % 2006 average consumption cereals expenditure expenditure in 2006 (CFAF) 6.8 21,338 1.6% (40) 6.8 21,338 1.6% (40) 4.9 15,376 1.2% (29) 7.7 24,162 1.8% (45) Source: Author. Note: The figures in parenthesis are US dollar equivalents. 258 Examining the distributional impacts of rice price changes by income groups and place of residence (Table 5-8), we observe some differences across income groups within the same location. Generally, across all income groups, the full welfare effects of rice price changes are higher in the urban area than in the rural area across all years. However, regarding the absolute magnitude of the welfare losses to households by place of residence and per capita income groups, we observe that in the urban area the absolute amount of the required compensation increases from the low- to the middle-income group but declines from the middle-income group to the high-income group (Table 5-9). The percentage reduction in total household consumption expenditures also declined from the low-income urban group to the high-income urban group, implying a negative relationship between per capita income group and percentage reduction in total household consumption expenditures as a result of a change in the price of rice. Table 5-8. Welfare Effects of Rice Price Increases by Place of Residence and Income Group (%) Urban First-order 2008 2009 2010 2011 12.2 12.1 9.0 12.8 2008 2009 2010 2011 14.5 14.8 11.5 16.2 2008 2009 2010 2011 Source: Author. 14.6 15.3 12.3 17.0 Rural Full Effect First-order Low Income 12.0 5.5 12.1 5.4 8.9 3.6 12.8 5.9 Middle-Income 14.2 6.9 14.6 6.7 11.4 4.7 16.1 7.5 High-Income 14.3 9.3 14.9 9.2 12.3 6.8 16.6 10.4 259 Full Effect 5.3 5.3 3.5 5.9 6.6 6.6 4.3 7.4 8.9 8.8 6.4 10.2 Table 5-9. Magnitude of Welfare Loss Implied by Rice Price Changes by Place of Residence and per Capita Income Group Year CV (Full impact) in % 2008 12.0 2009 12.1 2010 8.9 2011 12.8 2008 14.2 2009 14.6 2010 11.4 2011 16.1 2008 14.3 2009 14.9 2010 12.3 2011 16.6 Urban Value of Percent of compensation average total based on household 2006 average consumption cereals expenditure expenditure in 2006 (CFAF) Low-Income 34,382 2.5% (64) 34,669 2.5% (64) 25,500 1.9% (47) 36,674 2.7% (68) Middle- Income 52,287 2.0% (97) 53,760 2.0% (100) 41,977 1.6% (78) 59,284 2.3% (110) High-Income 43,785 0.9% (81) 45,622 0.9% (85) 37,661 0.7% (70) 50,827 1.0% (94) CV (Full impact) in % 5.3 5.3 3.5 5.9 6.6 6.6 4.3 7.4 8.9 8.8 6.4 10.2 Source: Author. Note: The figures in parenthesis are US dollar equivalents. 260 Rural Value of Percent of compensation average total based on 2006 household average consumption cereals expenditure expenditure in 2006 (CFAF) Low-Income 11,763 1.5% (22) 11,763 1.5% (22) 7,768 1.0% (14) 13,095 1.6% (24) Middle- Income 22,563 1.8% (42) 22,563 1.8% (42) 14,700 1.2% (27) 25,297 2.0% (47) High-Income 33,611 1.7% (62) 33,233 1.7% (62) 24,169 1.2% (45) 38,520 2.0% (71) Within the rural place of residence, we observe an increase in the percentage compensation based on average total cereals expenditures in 2006 (full effect) required from rice price changes as we move from the low- to the high-income groups. Additionally, we observe that the actual magnitude of the compensation based on average expenditure on cereals in 2006 increases from the low- to the high-income rural population groups (Table 5-9). In 2011 for instance, low-income rural households would need compensation of 13,095 CFAF (24 US $) to leave them indifferent to the price changes, the middle-income rural needed compensation of 25,297 CFAF (47 US $), while the high-income rural population needed compensation of 38,520 CFAF (71 US $). In terms of the percentage of the compensation in total household consumption expenditures, the welfare losses were almost of the same magnitude in the middle- and high-income rural population but lower in the low-income rural households. Thus, the high- and middle-income rural households would have had to be compensated by a slightly higher percentage of their total income following a change in the price of rice compared to the low-income households to leave their welfare unaffected by the price hikes. The explanation for this pattern is the increasing rice expenditure (Table 4-18) and expenditure shares (Table 4-19) as rural households get richer. Overall, we observe that all households are adversely affected by cereals price changes. However, considering all four cereals and the substitution between them, there are not many differences in the estimated full effects by place of residence and per capita income group in terms of relative shares of the cereals budget. Although the actual value of the welfare loss as a percentage of total household cereals expenditure in 2006 is higher amongst urban households than rural household, the magnitude of the welfare loss based on the percentage of average total household consumption expenditures were higher for rural households than urban households. 261 The analysis by place of residence shows that the adverse effect of the higher cereals prices on Malian population ranged from a 1.7 to 5.5% income reduction, without considering the possibility of producer supply response. Examining welfare losses by place of residence and per capita income groups reveals that in the urban population the percentage reduction in total household expenditure is lowest for the high-income group and largest for the low-income group. In the rural population, the welfare loss in terms of percentage reduction in total household expenditures in most cases declined from the low- to the high-income group. Because of its importance in the Malian food basket in terms of consumption shares, rice was isolated for the welfare impact evaluation to see whether there are any variations in welfare effect by place of residence. The full effect of rice price changes revealed that rice accounts for a substantial part of the overall welfare effect implied by higher cereals prices. Estimates of the full effect of rice price changes taking into account rice consumption share and the response of rice and other cereals to changes in rice prices show some heterogeneity in the impact of higher rice prices by place of residence. In terms of percentage in the 2006 average total household cereals budget, the burden of higher rice prices fell more on urban households than rural households. This result was not surprising giving that the share of rice in cereals budget was about 20% larger in the urban location than in the rural location. Examining the magnitude of the welfare loss from higher rice prices by place of residence reveals that although the actual amount of the compensation is higher for urban households than rural households, rural households would have to be compensated by a greater percentage of the average of their 2006 total household consumption expenditures than urban households. Still considering the welfare effects of rice price changes only, we observe a general increase in the full effect across per capita income groups within a particular place of residence 262 in terms of relative shares in the cereals budget. The distributional impacts of higher rice prices by income group and place of residence reveal a decline in the percentage income reduction from the low- to the high-income urban group. In the rural population, the reductions in total household expenditures emanating from higher rice prices are quite similar in the middle- and high-income group, but smaller in the low-income rural group. The increasing in welfare loss (in terms of percentage in total household expenditures) from a change in the price of rice from the rural low- to the rural high-income group reflects increasing rice expenditure and rice expenditure shares with growth in rural per capita income. 263 CHAPTER 6. SUMMARY OF MAJOR FINDINGS AND IMPLICATIONS FOR THE FOOD SECURITY POLICIES IN MALI 6.1. Summary of Major Findings and Policy Implications The goal of this study was to examine trends and determinants of food consumption patterns in West Africa and draw some implications for the design of food security policies. Knowledge of food demand parameters and of how consumption patterns have changed over time is critical for informed food policy making. However, in WA, information on food demand parameters is limited, thus restricting policymakers’ ability to make sound food policy decisions. One ultimate goal of the analysis of food consumption patterns is to improve the efficiency of government interventions by providing policymakers, for example, with suggestions for the design of food security policies compatible with targeting people based on the nature and extent of food insecurity. As defined by FAO (2006), “Food security exists when all people, at all times, have physical and economic access to sufficient, safe and nutritious food that meets their dietary needs and food preferences for an active and healthy life”. Food security is a broad concept which cuts across many dimensions. The four main dimensions of food security extracted from this definition are: sufficient quantities available for consumption, sustained access to food by each individual (adequate resources to obtain appropriate foods for a nutritious diet), effective utilization, and stable food supply (FAO, 2006). Simply put, people are food insecure when they do not “eat right” due to a lack of either physical or monetary access to food. Diaz-Bonilla et al. (2000) also observe that while food availability and access are preconditions for adequate utilization, they do not determine unequivocally the more substantive issue of malnutrition and 264 nutrition security at the individual level. Furthermore, from an economist’s point of view, access to food depends on income, prices, and distance to local food markets. Chapter 2 in this study explores physical food sufficiency, measured through aggregatelevel food supply indicators. Specifically, the chapter analyzes aggregate-level trends in per capita food availability in the ECOWAS countries of West Africa using a descriptive approach and per capita food availability data from FAO’s FBS covering the period 1980-2009. With respect to the aggregate-level trend in per capita daily energy availability (DEA), the analysis reveals: 1) an overall pattern of shift towards greater calorie availability in the region; 2) a remarkably positive growth in per capita DEA over time amongst the countries that have experienced strong economic performance, like Ghana and Nigeria; and 3) less favorable trends in per capita DEA in countries that have experienced civil disruption, like Liberia, Sierra Leone and Cote d’Ivoire. Per capita DEA has been widely used in the literature as one of the main determinants of national food availability (Smith and Haddad, 2000). As a national average, DEA is sometimes viewed as an imperfect indicator of the state of individual food security. However, empirical evidence, such as that provided by Smith and Haddad (2000), suggest that there is a strong correlation between this per capita DEA and more individual-based indicators of food security (e.g., anthropometric indicators of children’s nutritional status). In particular, Smith and Haddad (2000) show that national caloric availability was responsible for more than a quarter of reductions in child malnutrition in developing countries over the period 1970-95. Consequently, based on the observed trend in per capita DEA in the current study, one can say that there have been some improvements in the state of food security over the last three decades. The analysis of the trend in the composition of food supply over time provides evidence of a diversification in the composition of food supply. Starchy roots and tubers are emerging as 265 important contributors to the diets. In the Sahel for instance, we observe growth in percentage terms in starchy R&T availability per capita. However, this has been from a small base. The growth in the supply of starchy R&T has been greatest along the humid coast of WA. In some Coastal Non-Sahelian countries (Nigeria, Ghana, and Sierra Leone) there has been a big cassava revolution. The apparent per capita consumption of cassava grew in Senegal; that of sweet potatoes grew in Mali; and that of yams also showed huge increases in some Coastal NonSahelian countries (e.g., Ghana and Nigeria). The supply of Irish potatoes grew in some countries (e.g., Cape Verde and Senegal), while that of maize showed a striking growth in the Sahel (Burkina Faso, Mali and Senegal). Apparent per capita rice consumption increased for most countries in the study period. In Cape Verde for instance, there has been a replacement of maize with rice as the dominant type of cereal. These findings therefore present a scope to encourage ongoing diversification of staple food sources to give consumers more opportunity for substitution and choice. Not only have there been greater per capita availability of food and a diversification in the composition of the diet, but also the quality of food available has improved over time in terms of major macronutrient composition. Daily protein supply per capita has grown for most countries since the early 2000s. This study goes beyond examining the average per capita levels of total protein availability to disaggregate per capita protein availability by source. Protein quality varies by source, and animal proteins are generally of higher quality (essential amino acids) than protein from plant sources. Diaz-Bonilla et al. (2000) suggest that the availability of animal proteins is more directly correlated with measures of nutritional security than is the availability of total proteins. Animal protein supply has been increasing for some countries in the region. The growth in the supply of animal protein reflects greater purchasing power (effective 266 demand). In countries that have experienced rapid economic growth over time like Ghana and Cape Verde, the growth in the supply of animal protein has been remarkable. Countries with modest economic growth, such as Mali, have also shown modest growth in the consumption of animal protein over time. Decomposing animal protein by specific source, it is observed that growth in the apparent per capita consumption of poultry meat has been quite large for most countries in the region, although fish remains the dominant source of animal protein for most coastal countries. Furthermore, while plant protein dominates as the major source of protein for most countries in the region, some of these countries (e.g., Niger, Sierra Leone, Nigeria and Cape Verde) derive an important share of vegetable protein from pulses, which are also a source of high-quality protein. The positive growth in protein supply from pulses as well as in the share of pulses in daily vegetable protein supply supports the emergence of pulses as poor people’s meat in the region. This finding provides a scope to encourage and promote agricultural practices like crop rotation or intercropping of cereals with high protein grain legumes. Such agronomic practices will not only enhance soil fertility in an era of rising prices of inorganic fertilizers and climate change, but will also present an alternative to expensive animal protein, particularly for low-income households. Growth in the consumption of high quality plant protein would result in improvement in the nutritional status of poor households who cannot afford the expensive animal protein. Apparent per capita daily fat supply increased for most countries in the study period. There has therefore been some diet upgrading as the consumption of important macronutrients such as fats and protein have increased in the last three decades. The analysis of aggregate-level determinants of starchy staples demand (Chapter 3) after correcting for the unit roots properties of the data does not support any statistical association 267 between the urban population share and cereals consumption behavior in Senegal, but points to a statistically significant negative relationship between millet and urban population share in Mali. Evidence on the role of per capita income in influencing cereals consumption at the aggregate level reveals a statistically significant relationship between per capita cereals budget and rice and millet expenditure shares in the dynamic demand specification in Mali. The analysis also reveals no evidence in support of a statistical association between per capita income and starchy staples consumption in Senegal. The Hicksian cross-price elasticities from the error-corrected demand model provide evidence of a relationship of substitution in the short-run and long-run between rice and sorghum as hypothesized for Mali and Senegal. Furthermore for Mali, maize is found to be a substitute for rice and sorghum. In Benin, we observe\ a relationship of substitution between maize and yams in the short-run–both are used to make “fufu”, a basic carbohydrate main dish eaten with sauce. An implication of these statistically significant relationships of substitution is that they offer a scope to encourage ongoing diversification of starchy staples consumption, thereby giving consumers more opportunities for substitution and choices. Micro-level analysis in Chapter 4 gives us a closer look into the situation of food security at the household level. Using Mali’s 2006 HBS data, households’ economic access to food (measured by the household’s food expenditures) is examined alongside other factors at the household level to understand household food consumption behavior. Effective design of targeted actions requires knowledge of the distribution of the effects of changes in income as well as factors other than income that determine food demand — e.g., food prices and place of residence. To understand differences in cereals consumption by per capita income group, the rural and urban subsamples were each divided separately in thirds and households were assigned 268 to high, medium, and low-income groups for each type of residence, and demand parameters were estimated for each group. The demand for cereals is specified as a QUAIDS model which takes care of common problems in household demand estimation such as zero-expenditure and endogeneity in total cereals expenditure. The analysis in Chapter 4 reveals high expenditure elasticities for starchy staples. In particular, in the urban area, rice expenditure elasticity seems to have increased over time while the expenditure elasticity of sorghum is very high. With past findings that coarse grains are generally less preferred in the urban areas for various reasons such as the high opportunity cost of the time required for their preparation, the high sorghum expenditure elasticity warrants an investigation of consumer preferences for sorghum with different quality attributes. In the rural area, rice and millet are also high in expenditure elasticity. The high expenditure elasticities even for staples suggest strong future growth in demand and hence pressure on prices if supply is not increased. Therefore, the need to focus on driving down unit costs throughout the food system. Expenditure elasticities disaggregated by income-group and place of residence also reveal rice demand to increase in expenditure elasticity from the low- to the high-income urban groups. Millet and sorghum, on the other hand, become less preferred as urban households get richer, and the high expenditure elasticity obtained when all urban households are combined appears to be largely driven by the behavior of low-income urban households. In the rural areas, all four cereals increase in expenditure elasticity as households get richer. The findings of this study also provide scope to encourage ongoing diversification of staple food sources to give consumers more opportunity for substitution and choice. Sorghum demand was found to be the most responsive to own-price changes in the urban area. Also, disaggregating by income group, the demand for sorghum is most sensitive amongst the high 269 income urban group. If the high own-price elasticity of sorghum estimated represents urban Malian consumer behavior correctly, efforts geared towards expanding sorghum production and driving down the unit cost of production could encourage the consumption of sorghum Furthermore, the analysis reveals that for the range of prices observed in 2006, the price of rice appears to have a significant effect on the consumption of coarse grains in the urban area, whereby sorghum and millet are substitutes for rice. Thus, in the event of high rice prices, the consumption of traditional coarse grains in the urban areas can be encouraged by promoting the production of coarse grains (increased availability), and also by encouraging private sector involvement in the processing of these coarse grains to reduce preparation time. Further research can be carried out to investigate consumers’ preference for cereals with different quality attributes. Disaggregated across income groups and place of residence, the compensated crossprice elasticities point mostly to a relationship of substitution between the different cereals. This reveals not only a scope for dealing with price spikes for one cereal by increasing the availability of substitutes—a possibility that the earlier findings of low cross-price elasticities seemed to discount, but also a scope for price transmission across cereals across cereals. Thus, there is need for a cereals policy rather than just, for example, a rice policy. The welfare analysis of cereals price shocks in Mali over the period 2008-2011, taking into account the first order-response and the substitution responses, reveals not very large substitution effect for the reason that all cereals prices rose together. Estimates of the full impact reveal that all households are adversely affected by cereals price changes and the adverse effect of the higher cereals prices on Malian population ranged from a 2 to 6% income reduction, without considering the possibility of producer supply response. Disaggregating across income groups, the analysis reveals that in both the urban and rural population, low-income households 270 are hardest hit by cereals price increases–i.e., the percentage reduction in total household expenditure is lowest for the high-income group and largest for the low-income group. The decreasing expenditure elasticity of sorghum and millet as per capita income increase (discussed above), particularly in the urban area, and the willingness to substitute one cereal type for another implies that expanding the availability of these cereals could help reduce some of the welfare losses from cereals price shocks. The welfare losses from the recent price hikes imply a need to address supply (including marketing and processing) issues due to concerns about welfare and food security, as well as the likely impacts on economic growth of a likely reduced consumer spending on non-food items. 6.2. Limitations of the Study Despite the limitations outlined throughout the study, we can say that the key objectives of the study have been met in their essence. Yet, this study could be improved in many respects. Ideally, the analysis of household level food demand in a developing economy like that of Mali that has the rural population producing most of the food consumed in the country should go beyond measuring just consumption responses to measuring producer supply response to food price changes as well. Under the perspective of an agricultural household model, consumption behavior is complicated by production decisions. While most urban households are solely food consumers, most rural households are also food producers, such that changes in food prices affect them as consumers and producers. Furthermore, an increase in the price of a food commodity could increase the demand for that commodity (contrary to traditional demand theory) since a farmer may produce more of it and gain more income. Consequently, the net welfare effect of a price change depends on whether the household is a net-seller or net buyer of 271 food. Net food-selling households may see an increase in income that may compensate for the rise in the price of foods they purchase, while the net food-buying households are likely to be adversely affected by increases in the prices of foods they purchase. Unfortunately, as a result of data limitations, the analyses of cereals demand and the welfare effect of cereals price shocks in this study fails to account for the production or additional profit effect for food producing households that could accompany rising food prices. To carry out such analysis, one would need data on production by cereal type, production shares by cereal types, as well as input and output prices. Consumption patterns are determined by a combination of three factors: level of income, the preferences of households, and market prices. Preferences are in turn affected by the composition of the household, its members’ knowledge and education, habits and cultural norms, biological factors that affect hunger, etc. (Ruel et al. 2005). Two key assumptions of standard household demand models are that household resources are pooled and that the household has a single set of preferences. 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