Mont-89/malawi-maize-prices

# Maize Price Trends & Volatility Across Malawian Markets (2003–2026) An exploratory data analysis of maize retail prices in Malawi, using 20+ years of market price data from the World Food Programme. ## The question Maize is Malawi's staple food crop. This project asks four practical questions: 1. How has the maize price actually changed over time — and does it look different in local currency (MWK) vs. USD? 2. Is there a predictable seasonal pattern tied to the harvest calendar? 3. Do prices differ meaningfully between Malawi's regions? 4. Which markets have the least predictable (most volatile) prices? ## Key findings | Finding | Detail | |---|---| | **Currency distorts the story** | Nominal MWK price rose ~47x since 2003; USD-adjusted price rose only ~3.9x. Most of the "explosion" in price is currency devaluation, not a real shortage. | | **Strong seasonality** | Prices are ~60% higher in February (pre-harvest) than May/June (post-harvest), every year. | | **Regional gap is persistent** | Southern Region pays more for maize than Northern Region in almost every year recorded — a structural gap, not a one-off. | | **Volatility varies sharply by market** | Markets like Manyamula and Euthini are far less price-stable than markets like Chilumba and Lilongwe. | | **Data gap (2023–2024)** | No data was reported for these two years — flagged explicitly rather than smoothed over. | ## Charts - `figures/01_price_trend_mwk_vs_usd.png` — Nominal vs. USD-adjusted price trend - `figures/02_seasonal_pattern.png` — Average price by calendar month - `figures/03_regional_comparison.png` — Price by region, by year - `figures/04_market_volatility.png` — Most volatile markets (coefficient of variation) ## Data source WFP Food Prices for Malawi — Humanitarian Data Exchange (HDX), sourced from the World Food Programme Price Database. ~79,000 price records across 63 commodities and 129 markets, 1990–2026 (maize subset: ~14,000 records, 2003–2026). ## Tools Python, pandas, m …