Corn Fund Falls 2.9% After USDA Lifts Yield Forecast | Grains, Oct 9

Key Facts
- The corn fund CORN fell 2.85% to US$18.42 on Friday 9 October after the US Department of Agriculture (USDA) raised its US corn yield forecast to 181.2 bushels an acre, from 178.5.
- The USDA now sees US corn production at 16.034 billion bushels, up 234 million bushels, and ending stocks up 282 million bushels to 1.849 billion.
- The soybean fund SOYB rose 0.51% to US$27.53, while the wheat fund WEAT fell 1.41% to US$24.41.
- The USDA also raised its soybean forecast to 4.562 billion bushels, on a yield of 53.1 bushels an acre, from 4.535 billion and 52.8 in September.
Today’s Focus
Grain prices fell on Friday 9 October after the USDA’s monthly supply report, known as WASDE, lifted its corn forecast. The agency raised its forecast for the US corn yield to 181.2 bushels an acre.
The corn fund CORN fell 2.85% to US$18.42. The USDA also raised its soybean production forecast to 4.562 billion bushels, but the soybean fund rose 0.51% to US$27.53.
For Brazil and Argentina, big US crops mean more competition in world markets and lower prices for their corn and soybean exports.
What matters today. More US corn means lower prices for rival exporters.
01 The session in one read
The USDA raised the US corn yield to 181.2 bushels an acre, up 2.7 from September, lifting production by 234 million bushels to 16.034 billion. Ending stocks for 2026/27 rose 282 million bushels to 1.849 billion.
It raised its soybean forecast to 4.562 billion bushels on a yield of 53.1 bushels an acre, from 4.535 billion and 52.8 in September. All-wheat production rose to 1.534 billion bushels, from 1.531 billion.
The funds closed mixed: CORN down 2.85%, WEAT down 1.41% and SOYB up 0.51%. Grain traders ADM and Bunge fell 3.10% and 4.72%.
Corn felt the full weight of the bigger crop. A larger crop and larger stocks push prices lower until demand grows.
Soybeans held up, possibly because a large crop was already priced in. We cannot confirm that reading from a single session.
02 The board

| Asset | Level | Change |
|---|---|---|
| Corn fund CORN | US$18.42 | -2.85% |
| Soybean fund SOYB | US$27.53 | +0.51% |
| Wheat fund WEAT | US$24.41 | -1.41% |
| ADM | US$79.89 | -3.10% |
| Bunge | US$102.73 | -4.72% |
Source: RT close, 2026-10-09. The funds are futures-based and not spot prices.
The funds hold futures and are proxies for grain prices. The RT calendar listed the University of Michigan 1 Year Inflation Expectations (forecast 4.7%, previous 4.6%) and 5 Year Inflation Expectations (forecast 3.5%, previous 3.4%), and the USDA’s WASDE Report, for Friday 9 October; the Michigan actuals were not in the feed at our deadline. Rio Times · Live Market Intelligence
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03 What moved it: the WASDE report
The WASDE report is the USDA’s monthly view of world supply and demand. The October edition lifted corn supply well above September’s estimate.
Wheat fell too: the WEAT fund lost 1.41% to US$24.41.
ADM and Bunge, which process and trade grain, fell 3.10% and 4.72%. Bunge has large Brazilian operations.
04 The Latin American read
Brazil and Argentina compete with the US in corn, soybeans and wheat. A larger US crop weighs on world prices and on export income in both countries.
Brazilian farmers price in reais, so the real’s strength above 4.99 per dollar compounds the squeeze on local-currency revenue.
05 The names to watch
Bunge has operations across Brazil and Argentina. Its 4.72% fall, the largest on our board, shows the market’s worry about margins and volumes.
ADM is the other large trader and also fell sharply.
06 The outlook
The next catalysts are harvest progress and Chinese buying. Harvests in the US were delayed this autumn, according to DTN, so yield estimates could still change.
Large stocks mean any weather shock would be needed to push prices higher.
07 What to watch
- US harvest progress: Delays could cut yields from the USDA’s forecast.
- Chinese buying: Purchases of US soybeans would test the price.
- The real: A stronger real hurts Brazilian exporters.
- November WASDE: The next USDA update will revise today’s numbers.
Background: Wheat, Corn and Soy Funds Slip Before WASDE | Grains, Oct 8.
Frequently Asked Questions
Why did corn fall on 9 October 2026?
The USDA raised its yield forecast to 181.2 bushels an acre, from 178.5 in September. The corn fund fell 2.85%.
What is WASDE?
WASDE is the USDA’s monthly World Agricultural Supply and Demand Estimates report on crop supply and demand.
How does a big US crop affect Brazil?
It adds supply in world markets and lowers prices for Brazil’s corn and soybean exports.
What do the grain funds track?
CORN, SOYB and WEAT hold futures contracts on corn, soybeans and wheat, so they follow futures prices, not local cash prices.
Market data: RT; WASDE figures: USDA; harvest delays: DTN; prediction markets: none found for grains
This article was produced by The Rio Times’ automated newsroom system. How we use AI · Report an error · Editorial responsibility: Matthias Camenzind, Editor-in-Chief
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