Crop Year vs Calendar Year in Commodity Markets

Commodity analysts rarely use calendar-year (January–December) figures; instead, they track crop year vs. calendar year data aligned to the harvest season. A corn crop year runs September to August; wheat is June to May; soybeans are September to August. This harvest-based calendar matches supply realities and avoids artificial splits across two growing seasons, making it essential for understanding commodity pricing cycles, storage dynamics, and carry-forward inventory.

Why Harvest-Based Accounting Matters

Commodity prices and supplies are dictated by harvest cycles, not the calendar. When you buy corn futures in January, that contract reflects supplies from the previous year’s harvest (which occurred in September–October) plus expectations for the next harvest (due in September–October of the current calendar year).

Using calendar-year data obscures this reality. A January–December snapshot might show supplies from two different crops mixed together:

• January–August: tail end of the prior crop year
• September–December: the start of the new crop year

This creates a meaningless hybrid figure. Instead, commodity markets and analysts use crop year (also called marketing year) accounting, which runs from harvest to harvest, aligning supply, demand, and pricing within a single growing/harvesting season.

The U.S. Corn Crop Year: September to August

U.S. corn is harvested primarily in September and October. The crop year runs September 1 to August 31.

Key milestones:

• September–October: The bulk of the U.S. corn harvest hits the market. Supply jumps; prices typically fall as the market absorbs the new supply.
• October–August: The remainder of the crop year. Corn is stored, processed, exported, and consumed. Prices are driven by storage costs, competing supplies, and demand.
• End of August: The USDA publishes its final “Stocks Remaining” report for the crop year. This is the critical figure—how much corn will carry over into the new crop year, starting September 1.

A typical U.S. corn crop year looks like:

Prices often peak in June–August (the “tight supply” window before the new harvest) and trough in September–October (new harvest surplus).

Why Calendar Year Reporting Would Be Misleading

If a corn analyst reported “2024 U.S. corn supply,” using January–December 2024, the number would include:

• January–August 2024: Old crop (harvested September–October 2023)
• September–December 2024: New crop (harvested September–October 2024)

These are two different harvests, with different yields, supply outlooks, and price drivers. Mixing them distorts your understanding of the current market.

In contrast, reporting “2024–2025 crop year” (September 2024–August 2025) captures a single, coherent harvest and its supply cycle. Everyone analyzing the market uses this lens.

Other Major Commodities and Their Crop Years

Wheat: June 1 to May 31
Winter wheat is harvested in June–July in the Northern Hemisphere (U.S., Europe). The crop year aligns with this harvest. Prices often peak in May (just before harvest supply arrives) and trough in July (new harvest glut).

Soybeans: September 1 to August 31
Soybeans are harvested in September–November in the U.S., on the same calendar as corn. The crop year is therefore the same: September to August. However, Argentine soybeans (harvested March–May) are sometimes tracked on a different marketing year (April–March) to match that hemisphere’s harvest.

Sugar: October 1 to September 30
Sugar crops are harvested at different times globally, but in major producer regions (Brazil, India, EU), the harvest season is October–March. The crop year is typically October–September.

Cocoa: October 1 to September 30
Cocoa pod-harvesting seasons vary by region (some year-round production), but the main crop year for pricing is October–September, aligned to the West African harvest (the world’s largest supply source).

Coffee: October 1 to September 30
Coffee crop years vary by origin (Brazilian vs. Colombian harvests are staggered), but the trading convention is October–September, and prices are typically quoted by “crop year” rather than calendar year.

Carry-Forward (Carryover) Stocks

One of the most important metrics in commodity markets is carryover stock or carry-forward inventory—the supply left over at the end of the crop year, available to be stored and used in the next crop year.

Example: At the end of the 2024–2025 corn crop year (August 31, 2025), the USDA estimates 2.1 billion bushels of corn will remain in storage. This is the carryover stock, fed into the next crop year’s (2025–2026) opening supply.

Carryover is measured at the END of the crop year, not the calendar year. This is why crop-year accounting is critical. If you measured carryover at December 31, it would include supplies from multiple harvests and obscure the true inventory picture.

High carryover stocks tend to weigh on prices (abundant supply available at the start of the next crop year). Low carryover stocks (below 10% of annual use) can spike prices and create supply concerns.

Futures Contracts and Crop-Year Terminology

Commodity futures contracts are often labeled by crop year:

• “Old crop” or “old-crop corn” = a contract that expires before the new harvest arrives (e.g., July corn futures expire in July, before the September harvest).
• “New crop” = a contract that expires after the new harvest (e.g., December corn futures expire in December, after the September–October harvest).

Old-crop and new-crop contracts can trade at different prices, especially during the harvest transition. New-crop contracts typically trade at a lower price than old-crop if supplies are expected to be ample, reflecting the cost of storage and the passage of time.

Understanding this terminology requires thinking in crop years, not calendar years.

How Commodity Prices Respond to Crop-Year Cycles

The typical price trajectory within a crop year follows supply/demand dynamics tied to the harvest and season:

1. At/just before harvest (September–October for corn): New supply hits; prices fall as buyers absorb the glut.
2. Post-harvest (November–February): Prices stabilize. Storage demand (farmers pay to hold grain) can support prices. Exports are active.
3. Spring (March–May): Demand is steady. Prices may drift higher if exports or feed use is stronger than expected, drawing down stocks.
4. Late season (June–August): Supplies tighten. Carry-forward stock concerns emerge. Prices often peak.
5. New harvest arrives (September): Cycle resets.

Commodity traders track this seasonal pattern religiously, and many trading strategies are built around crop-year supply cycles.

Global Harvest Differences and Crop-Year Misalignment

A complication: the world does not harvest all at once. Argentina’s soybean harvest is March–May (fall in the Southern Hemisphere); the U.S. harvest is September–October. Global supply discussions must account for both.

International commodity agencies (like the FAO) publish supply reports that aggregate global crops, typically reconciling them to a single crop year (often a July–June “global crop year” or regional aggregations). But any forward-looking commodity analysis must respect the hemisphere-specific harvest cycles.

For example, a corn shortage in early 2025 (Northern Hemisphere winter) might be offset by Argentine corn supplies in March–May (Southern Hemisphere harvest). Commodity traders and policymakers track both crop years to forecast global supply balances.

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