The USDA unexpectedly raised the U.S. corn yield in the October supply and demand report to a national average of 176.5 bushels per acre, one-half bushel above the average trade guess. This was enough to put yearly production at 15.02 billion bushels, 20 million bushels higher than the September prediction. 

Very few changes were made to corn demand, which put ending stocks at 1.5 billion bushels, up 100 million bushels from September. This is a 10.1% stocks-to-use and requires less rationing. 

Bigger changes took place in soybean balance sheets, adding to an already negative tone in the complex. 

The average U.S. soybean yield is now pegged at 51.5 bushels per acre, compared to the 50.6 bushels per acre estimate last month. This brought production to 4.45 billion bushels, a 74 million bushel increase on the month. 

The only change to demand was a 10 million bushel increase in crush, which put ending stocks at a comfortable 320 million bushels. This is a...