2011年-世界发展银行全球_Agricultural_Distortions_in_Sub-Saharan_Africa___Trade_and_Welfare_Indicators_1961_to_2004_28页_378kb

Summary of "Agricultural Distortions in Sub-Saharan Africa: Trade and Welfare Indicators, 1961 to 2004"

Core Content

This paper analyzes the trade and welfare effects of agricultural price and trade policies in 19 Sub-Saharan African countries from 1961 to 2004. It introduces and applies modified trade restrictiveness indexes to quantify the distortions caused by government interventions in agricultural markets. These indexes provide a theoretically sound and empirically precise way to assess how agricultural policies have impacted trade and economic welfare over time.

The study focuses on three types of indicators:

• Country-level trade and welfare reduction indexes (TRI and WRI), which capture the overall effect of agricultural policies on trade and welfare.
• Policy instrument trade and welfare reduction indexes (ITRI and IWRI), which break down the contributions of different policy tools to trade and welfare distortions.
• Commodity market trade and welfare reduction indexes, which evaluate the relative distortions across different agricultural commodities in the region.

Main Views and Key Findings

1. Agricultural Policies in Sub-Saharan Africa

• Agricultural price and trade policies in Sub-Saharan Africa historically imposed significant distortions on trade and welfare.
• These policies often taxed farm household earnings, especially from export commodities, and were prevalent across many developing regions until the early 1980s.
• Despite reforms, especially in reducing export taxation, national policies continue to reduce trade and welfare more than in Asia or Latin America.
• Around 60% of the workforce in Sub-Saharan Africa is employed in agriculture, and over 80% of the poorest households depend on farming for their livelihoods.

2. Methodology

• The paper uses a modified version of trade restrictiveness indexes to measure the impact of agricultural policies.
• These indexes are derived from nominal rates of assistance (NRA) and consumer tax equivalent (CTE) data from the World Bank's Distortions to Agricultural Incentives database.
• The TRI and WRI are calculated using weighted averages of price distortions on the producer and consumer sides of the market, with the WRI being a mean of order two and thus more reflective of welfare costs.
• The paper extends the methodology to include nontradable products, which are significant in many African economies.

3. Policy Instruments

• Four types of border distortions are considered: import taxes, import subsidies, export taxes, and export subsidies.
• The ITRI and IWRI are constructed to assess the trade and welfare impacts of each policy instrument individually.
• These indexes are based on the assumption that border measures are applied first, and domestic distortions are residual effects. This provides a lower bound for welfare losses from border policies and an upper bound for domestic ones.

4. Commodity Market Analysis

• The study also evaluates regional commodity market distortions, contrasting the effects of policies on different agricultural products.
• The regional commodity TRI and WRI are calculated to show how individual commodities are affected by national policies across the region.
• These indexes take into account both border and domestic price distortions, and include import-competing and exportable countries in the analysis.

Key Information

• The Distortions to Agricultural Incentives database provides consistent measures of price-distorting policies for 75 countries, including 21 in Africa.
• The paper excludes Egypt and South Africa due to their relative affluence.
• The focus countries include:
  • Eastern Africa: Ethiopia, Kenya, Sudan, Tanzania, Uganda
  • Southern Africa: Madagascar, Mozambique, Zambia, Zimbabwe
  • West Coast of Africa: Cameroon, Côte d'Ivoire, Ghana, Nigeria, Senegal
  • West and Central Africa: Benin, Burkina Faso, Chad, Mali, Togo
• The NRA and CTE data covers 41 agricultural products, accounting for 70% of each country's total agricultural production.
• The TRI and WRI are computed annually, beginning from 1961, as data before that year is incomplete.

Data and Trends

• The weighted average NRA for the 19 focus countries is almost always negative, indicating that government policies have generally reduced farmers' earnings.
• The average rate of consumer price distortion is positive, reflecting the tax burden on consumers.
• The standard deviation of NRAs across industries indicates the variability in policy impacts, with greater dispersion suggesting more significant welfare losses.
• The tradables share of the gross value of production for covered agricultural products in the focus countries ranges from 31% to 43% over the period.

Conclusion

• The study highlights the persistent negative impact of agricultural policies on trade and welfare in Sub-Saharan Africa.
• It demonstrates the progress made in policy reform, particularly through the reduction of export taxation.
• The methodology introduced provides a more accurate and timely way to assess agricultural policy distortions compared to computable general equilibrium (CGE) models, which are data-intensive and infrequently updated.
• The paper emphasizes the importance of monitoring these policy changes to support agricultural development and poverty reduction efforts in the region.