20% of farmers are big enough to skip the wholesalers and sell internationally. The other 80% sell to local wholesalers to sell internationally. And even th

20% of farmers are big enough to skip the wholesalers and sell internationally. The other 80% sell to local wholesalers to sell internationally. And even though most wheat et al is consumed in the US, a significant amount is exported. A small drop in demand can have a massive impact on price. "100 supply, 101 demand: price goes up. 100 supply, 99 demand: price goes down."