Painting Price: Price Discovery in Segmented Markets: Evidence from the Nairobi Coffee Exchange

We investigate the dynamics of price discovery between physical spot and financial futures markets for green coffee, a commodity uniquely characterized by the geographical and informational separation of its producers from global financial centers. Using dis-aggregated weekly prices from the Nairobi Coffee Exchange (NCE) auction and corresponding International Coffee Exchange (ICE) futures, we estimate a vector error correction model to quantify the transmission of information. Our findings reveal that price discovery predominantly occurs in the physical spot market, which accounts for approximately 83% and 88% of the information and component shares, respectively. These results challenge the conventional view that futures markets are the primary locus of price formation for homogeneous commodities and highlight the critical role of local supply-demand fundamentals in a major producing region. The analysis further uncovers heterogeneity in price discovery contributions across different coffee grades, providing novel insights into the micro-structure of agricultural commodity markets.