Market surprise.
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Today’s post reviews the evidence from our report about potential problems with USDA corn stocks estimates. This is the second in a series of farmdoc daily posts discussing the findings in the recent report, which can be found here. The research was funded by the Office of the Chief Economist of the USDA. We begin with a brief overview of the USDA grain stocks estimates.

USDA Grain Stocks Estimates

The National Agricultural Statistics Service (NASS) of the USDA provides estimates of U.S. corn and soybean inventories at the end of each quarter of the marketing year. The reference dates for those estimates are December 1, March 1, June 1, and September 1. Estimates of on-farm grain stocks (inventories) are based on data collected in the quarterly Agricultural Surveys in which a sample of producers are asked to identify the storage capacity of all structures normally used to store whole grains or oilseeds and to estimate the total number of bushels stored on the reference date on the total acres operated by the respondent regardless of ownership or intended use of the crops.