The National Agricultural Statistics Service said on Friday that it had found a processing error affecting September 2026 corn plant populations, ear counts, yields and production for Kansas and Nebraska, along with September averages across 10 states and the United States corn yield and production forecasts, AgWeb reported. The agency corrected the affected September data in its Crop Production reports and Quick Stats database, but did not say exactly what the error was or why it happened.
The corrections change the story the autumn reports told. Nebraska’s September corn yield was raised by 5 bushels an acre, from 177 to 182 bushels, which cuts the month to month jump in the October report from 11 bushels to 6. The United States September average was lifted from 178.5 to 178.8 bushels an acre, and Kansas’s September yield was cut from 121 to 119 bushels an acre. NASS said its October forecasts, released on October 9, were reviewed and validated and have not changed: the national yield estimate stays at 181.2 bushels an acre and total production stays above 16 billion bushels, put at 16.034 billion bushels in the corrected reporting.
That sequence is what angered growers. The October report had caught the corn market off guard and triggered a sharp sell off, and the National Corn Growers Association and state groups called the error unacceptable, arguing that the market moved on an October increase that the corrected September baseline now shows was smaller than reported. With the production forecast held above 16 billion bushels, cash bids and basis in the eastern Corn Belt remain under pressure from the heavy paper supply, at a point in harvest when growers are deciding whether to sell off the combine or pay for storage.
Corn settled at 456.0 cents a bushel in the site market tables updated October 25, down 0.98 percent on the day and 3.85 percent on the week. The dispute is now about trust in the series itself: the next test is whether the November Crop Production report revisits the October number the agency has just validated.