# A corn market surprise puts USDA data accuracy in focus

> USDA corrected its September 2026 corn production estimates after a processing error in Kansas and Nebraska. The correction raised September national production by 28.4 million bushels, and it followed some of the largest single-day declines in December corn this year.

- Date: 2026-11-02 · published 2026-11-02T21:05:43.268Z
- Category: report · region US · magnitude medium
- Page: https://feedsoft.ai/events/75765-a-corn-market-surprise-puts-usda-data-accuracy-in-focus
- Commodities: [Corn](https://feedsoft.ai/c/CORN.md)

## Why it matters

Revised USDA numbers change the expected size of the crop and shift price expectations for corn feed buyers. The correction reduces the reported September-to-October production increase.

## Read by commodity

- CORN: neutral

## Similar past events

| Commodity | Date | Event | 5-day % | 20-day % |
| --- | --- | --- | --- | --- |
| CORN | 2022-01-12 | [Markets mixed on USDA data](https://feedsoft.ai/events/43102-markets-mixed-on-usda-data.md) | -2.6% | +3.6% |
| CORN | 2019-01-01 | [Market Reaction to USDA’s August Corn Crop Reports](https://feedsoft.ai/events/60954-market-reaction-to-usda-s-august-corn-crop-reports.md) | +1.4% | +1.8% |
| CORN | 2020-08-12 | [Corn, soybeans rise after USDA confirms massive US crops - Markets - Business Recorder](https://feedsoft.ai/events/51546-corn-soybeans-rise-after-usda-confirms-massive-us-crops-markets-business.md) | +3.8% | +8.3% |
| CORN | 2023-10-19 | [USDA defends ballooning US corn yield estimates in data meeting](https://feedsoft.ai/events/13243-usda-defends-ballooning-us-corn-yield-estimates-in-data-meeting.md) | +1.0% | -2.6% |
| CORN | 2026-06-01 | [US: USDA Supply/Demand - Corn](https://feedsoft.ai/events/19196-us-usda-supply-demand-corn.md) | -5.5% | -10.2% |

## Sources

- wisfarmer.com: https://www.wisfarmer.com/story/news/2026/11/02/usda-crop-estimate-mistake-sent-shockwaves-through-corn-trade/92522264007/

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Data from Feedsoft AI (https://feedsoft.ai/). For information only; not investment advice.