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By: Editorial Team, StoneX Media
Private fund yield models for corn now run well above the U.S. Department of Agriculture's own estimate, and that single divergence is steering the billions of dollars that funds hold across the commodity complex. The reason private corn yield estimates sit higher than the U.S. Department of Agriculture figure is that funds build or buy their own yield models and trade those projections directly, rather than waiting on the official number. With crude oil and grains selling off together on geopolitical headlines, the move looks more headline-driven than fundamental, and the money is following the models and the algorithms rather than the balance sheet. That gap is not fixed, either, since a sharp drop in the weekly crop ratings can pull some yield models lower, depending on how each is built, even as improved August weather pulls the other way. For grain producers and commercial buyers, that means fund positioning is shaping the corn and soybean market as much as the underlying balance sheet.
Arlan Suderman is Chief Commodities Economist at StoneX, where he oversees the firm's commodity market intelligence and analyzes global macro-economic trends across agriculture, energy, and metals markets. His work tracking crop production, grain marketing, and risk management, built over a career that began with the Kansas Extension Service and included market analysis roles at Farm Futures and Water Street Solutions, connects directly to how funds and the U.S. Department of Agriculture arrive at differing corn yield estimates.
"All of the ones that I've seen are well above where USDA is at", Arlan Suderman said of the private corn yield models that grain funds rely on. Private fund yield models now project corn output above the U.S. Department of Agriculture estimate, and it is the model number that funds trade rather than the government figure. Corn and soybean prices are being set by projections that assume a larger crop than the official data currently shows. That gap is not static, though, because a sharp drop in the weekly crop ratings can pull some of those yield models lower, depending on how each one is constructed. Fund managers then weigh any such downgrade against the improved August weather models, so a weaker ratings print does not automatically lift corn and soybean prices. That leaves grain producers exposed to a market pricing yields they may not welcome, while end users benefit from the softer tone those models create.
Grain funds with billions of dollars at stake in the commodity markets construct or license their own yield models to guide their positions. The funds, Suderman explained, will either "spend a lot of money developing yield models" or subscribe to an outside service, then trade whatever crop size those models produce. That behavior turns strong early yield readings into a money-flow story, and when a weekend of geopolitical headlines hits, the algorithms move that fund capital into or out of the grain and oilseed complex faster than any fundamental shift would justify. When the models point to a bigger crop, the selling can build quickly, which is one reason grain prices have fallen even as some supply risks remain unresolved. For commercial buyers, the signal is that fund positioning, not the balance sheet alone, is moving the corn and soybean market they operate in.
August weather now holds the biggest sway over whether corn and soybean yields hold near the levels the fund models assume. The weather models have shifted in a more favorable direction for the crop, which supports the higher private yield projections and keeps downward pressure on grain prices. A spell of intense heat can still knock the weekly crop ratings lower across the western Corn Belt, and fund managers set that weaker read against the more favorable August outlook rather than reacting to either alone. That western skew means the national crop can still come in large even as individual states post yield losses, which is exactly what the futures market is weighing. According to Suderman, the outlook can turn fast, as "that could all change at any moment as if the weather models flip, but for now they're looking more favorable".
Above-trend yield models point to a larger total crop, and the futures market prices that total directly rather than the state-by-state detail. The cash and basis markets are where differences between states get resolved, since supplies still need to move to meet demand. A bigger projected crop tends to keep downward pressure on corn and soybean prices until the yield models or the weather shift.
The U.S. Department of Agriculture publishes weekly crop condition ratings each Monday after the market closes, and those ratings feed straight into the yield models that funds run. Some of those models also build in weather data while others do not, which is part of why fund projections can diverge from the government estimate. When the ratings drop sharply, the models that absorb them tend to come down too, though fund managers weigh that decline against the improved weather models before adjusting their positions.
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--- Written by Gus Farrow, Senior Manager, StoneX Media
--- Expert: Arlan Suderman, Chief Commodities Economist
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Grain funds are trading privately built corn yield models that run well above the U.S. Department of Agriculture’s own estimate, and that gap is driving money into and out of the market. Understanding why those models diverge explains more about the corn and soybean price swings than the weekend headlines the algorithms chased.
July 28 – Stock futures were mixed to firmer overnight, as relative calm continues in the Middle East and as the Federal Open Market Committee begins two days of monetary policy discussion. The VIX is trading near 19, while the dollar index trades near 101.5. Yields on 10-year Treasuries are trading near 4.63%, while yields on 2-year Treasuries are trading near 4.30%. WTI crude oil is trading near $81 per barrel after actually probing below $80 earlier in the session, while Brent trades near $87 per barrel. The grain and oilseed sector tried to bounce in the overnight session following yesterday’s active selloff, but it quickly succumbed to additional selling pressure as crude oil added to its losses, with the exception of corn that held modest gains based on tumbling crop ratings.
July 27 – It was a quiet weekend for Iran, which investors interpreted as a sign that there’s still a chance for peace in the Middle East. Yet, Iran-backed Houthi rebels attacked Saudi Arabian oil facilities in the Red Sea, providing a reminder that risks remain significant. Even so, overnight market action again reflected sentiment that investors continue to read headlines through a filter of hope – desperately wanting to believe that peace is just around the corner. Commodity prices tumbled overnight while stock futures pushed higher, with the VIX slipping below 18 and the dollar index trading near 101.4. Yields on 10-year Treasuries traded near 4.65%, while yields on 2-year Treasuries traded near 4.32%. WTI crude oil is trading near $84 this morning, although that’s a couple of dollars off its session low, while Brent trades near $91 per barrel. The grain and oilseed markets were mostly weaker overnight as well, following crude oil prices lower, while also reacting to improving weather models for the Midwest as we approach the key crop development month of August.
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