Information Rigidity and Correcting Inefficiency in USDA’s Commodity Forecasts

This study investigates the rationality of monthly revisions in annual forecasts of supply, demand and price for U.S. corn, cotton, soybeans, and wheat, published in the World Agricultural Supply and Demand Estimates over 1985/86-2010/11. The findings indicate that USDA's forecast revisions are not independent across months, and that forecasts are typically smoothed. Adjustment for smoothing in a subset of forecasts (1998/2000-2010/11) showed mixed results: significant improvements for soybean use forecasts, cotton exports, and a broad cross-section of forecasts published in October. However, accuracy deteriorated in some cases, particularly for late-season preliminary data revisions.