Is Storage at a Loss Merely an Illusion of Spatial Aggregation?

The storage-at-a-loss paradox—stocks despite inadequate price growth to cover storage costs—is an unresolved issue of long-standing interest to economists. Alternative explanations include risk premiums for futures market speculators, convenience yields from holding stocks, and mismeasurement/aggregation of data. Statistical analyses of regional and elevator corn and soybean price growth in Illinois suggest limited aggregation effects and reveal a pattern of regional- and elevator-level backwardations in the presence of Illinois corn stocks that is inconsistent with aggregation explanations for storage at a loss. Interviews with elevator managers support the existence of convenience yields.