Key findings
- Measured storage losses explain a minority of seasonal wedges; credit constraints and inventory risk dominate at the trader tier.
- Interventions that only subsidize sacks without addressing trader working capital show limited pass-through to producers.
Market structure
Cowpea moves through layered assembly markets with thin inventories. We document how traders’ opportunity cost of capital shapes the harvest–lean season spread independent of on-farm losses.
Methods
Loss audits at cooperative stores are paired with trader ledger reconstruction and spatial price panels. A decomposition attributes wedges to observable loss, inventory financing, and unobserved quality sorting.