USDA yesterday officially declared that the long bull market in corn is finished. It did so by increasing old crop supplies by 50 million bushels and deciding on 10 May that the U.S. corn yield will set an all-time record of 166 bushels per acre. The path to this declaration was established back in the April WASDE, when USDA did not reduce old crop ending supplies despite a smaller-than-expected 1 March quarter corn stocks number. That number can't be verified until the 1 June quarterly stocks number is released on 29 June. There will be too much water under the bridge by that point for the 1 June number to make much difference unless weather between now and then has changed and the market believes the 166-bushel yield projection is threa...