· Analytic
Z4393 US Corn Ending Stocks YoY INV (Publication-Lag Aware)
The year-over-year change in US corn ending stocks, with each marketing year’s value anchored at Oct 1 of the FOLLOWING year , when the September Grain Stocks report and October WASDE have reconciled the final number. The pre-patch engine anchored at Aug 1 of the marketing year’s starting year, a 14-month look-ahead that materially inflated in-sample statistics.
Current reading
-0.830
Moderate Neg
DAILY · SIGNAL
As of Oct 30, 2026. Updated nightly.
Current composite
-0.8541
Publication-lag-aware signal; US corn stocks reconciled as BUILDING YoY
Signal state
Moderate NEG
116 consecutive days in state (sustained since 2026-05-11)
Pre-patch comparison
-0.8541 (patched) vs +0.9290 (pre-patch)
Full-direction flip after look-ahead removed
Latest reconciled YoY
+25.4%
MY 2024 → MY 2025 ending stocks reconciled Oct 2026 (public knowledge as of patch date)
Baseline corn fwd 60d
-0.48%
Unconditional mean across 8,979 trading days
Pre-patch Corn Cycle DNA contribution
-0.139 → +0.128
Full-direction flip into Corn Cycle DNA composite
Days since last event
115
Last event: May 11, 2026
Nearest threshold
+0.65
To cross into Neutral
Typical run length
352 days
Based on 9 historical Moderate NEG runs; 25-75 pct range: 191-414 days
OBJECTIVE
The US corn WASDE ending-stocks figure is the single most-watched grain supply-and-demand number in the monthly USDA cycle. Each World Agricultural Supply and Demand Estimates publication prints a top-line US corn ending-stocks number by marketing year, and that line is parsed by every grain-trading desk globally within minutes of release. The number is PROJECTED starting in May of the marketing year’s starting calendar year (approximately 4-5 months before the crop is harvested) and progressively REVISED monthly through the subsequent 18 months as production is finalized and consumption is reconciled. The FINAL reconciled ending-stocks number for marketing year MY (which runs Sep MY through Aug MY+1) is reasonably public knowledge by Oct 1 of year MY+1 , after the September Grain Stocks quarterly report and the October WASDE revision. This signal uses that Oct 1 of MY+1 anchor for its YoY calculation. The pre-patch engine anchored at Aug 1 of year MY (14 months BEFORE the final number was knowable), a look-ahead that was materially inflating the engine’s in-sample statistics. The 2026-10-25 patch applied the publication-lag-aware anchor. The signal reads minus 0.854 as of October 23, 2026, in MODERATE_NEG territory for 116 consecutive trading days. The reading reflects the latest publicly-reconciled YoY (MY 2024 → MY 2025, reconciled October 1 2026) which shows US corn ending stocks BUILT approximately 25 percent year-over-year , a BEARISH signal for corn forward returns. The pre-patch engine was showing EXTREME_POS +0.929 (bullish for corn) by reading the MY 2026 ending-stocks PROJECTION (not reconciled until October 2027), a classic look-ahead artifact. The signal contributes 15 percent weight to Corn Cycle DNA with polarity sign minus one; the current contribution to Corn Cycle DNA is plus 0.128 (changed from minus 0.139 pre-patch, a full-direction flip). Read on for the publication-lag methodology, the three signature historical cases, and the current reading in context.
LIVE CHART
Sixty-six years of US corn ending-stocks YoY dynamics with publication-lag-aware anchor.
The signal has been in MODERATE_NEG for 116 consecutive trading days through October 23, 2026, with the composite reading at minus 0.854. The latest publicly-reconciled YoY (MY 2024 → MY 2025, reconciled Oct 1 2026) shows US corn ending stocks BUILT approximately 25 percent year-over-year, which is a historically-bearish reading for corn forward returns. The pre-patch engine was reading the MY 2026 ending-stocks PROJECTION (not reconciled until October 2027) and showing EXTREME_POS +0.929 , a look-ahead artifact that the 2026-10-25 patch removed.
COMPOSITE
-0.9 / 100
STATE
Moderate Neg
PHASE
-1
FWD 60d
+6.91% (baseline +2.31%)
SAMPLE N
9,039 days
TODAY’S PLAYBOOK READING
STATE
Moderate Neg
STATE AND PRE-PATCH COMPARISON
MODERATE_NEG at minus 0.854 post-patch versus EXTREME_POS plus 0.929 pre-patch. Full-direction state flip after the 14-month look-ahead was removed.
WHY THE SIGNAL IS HERE
Latest reconciled US corn ending stocks YoY (MY 2024 → MY 2025, Oct 2026 WASDE) shows approximately +25 percent stocks build driven by the large 2024 US harvest working through consumption at modest rates. The build is bearish for corn forward returns in the historical pattern.
POSTURE FOR THE WEEKS AHEAD
The next WASDE publication cycle may begin incorporating MY 2026 (new-crop) PROJECTIONS which would progressively anchor approximately October 2027 at the earliest. Intra-year dynamics will reflect September 2027 Grain Stocks reconciliation. Current MODERATE_NEG state historically delivers below-baseline corn forward returns.
WHAT THE CHART SHOWS
The composite sits at -0.83 in the Stocks Loosening band (moderate-neg). The blue signal line has been in the loosening band since the October 2026 WASDE and September Grain Stocks reports reconciled the 2025-2026 marketing year with 2025 US corn ending stocks UP meaningfully year-over-year. CBOT front-month corn (orange, right axis) sits near $4.48/bu.
TOP INPUTS FIRING
- Primary composite -0.83 State Stocks Loosening, moderate-neg band; 2025-2026 marketing year closed with ending stocks UP YoY per October 2026 WASDE reconciliation.
- US corn ending stocks YoY, publication-lag aware Each marketing year’s value anchors at October 1 of the following year, when the September Grain Stocks report and October WASDE have reconciled the final balance.
- IC vs CBOT corn fwd 60d: Spearman +0.0923, p=1.9e-18 (N=8,984) Significantly positive IC: positive composite (stocks tightening) predicts positive corn fwd 60d; the fundamental supply mechanism works.
THE TAKEAWAY
What this means for you today
WHAT THE PUBLICATION-LAG-AWARE READING IS TELLING YOU
The patched signal reads approximately -0.85 (MODERATE_NEG) as of October 23 2026, reflecting the latest publicly-reconciled US corn ending-stocks YoY. The marketing year MY 2024 ran September 2024 through August 2025; its ending-stocks number was finalized via the September 2025 Grain Stocks quarterly and the October 2025 WASDE. Similarly MY 2025 was reconciled via September-October 2026 publications. The YoY from MY 2024 to MY 2025 shows an approximately 25 percent stocks build. This is a BEARISH signal for corn forward returns in historical empirical terms, which is why the patched engine registers negative composite values.
THE 14-MONTH LOOK-AHEAD THE PATCH REMOVED
The pre-patch engine anchored each market year’s YoY value at `Timestamp(MY)-08-01` , August 1 of the marketing year’s STARTING calendar year. For market year MY 2026 (which runs September 2026 through August 2027), the pre-patch engine placed the YoY anchor at August 1 2026 , 14 MONTHS BEFORE the MY 2026 ending-stocks number can realistically be reconciled (reconciliation requires the full September 2026 to August 2027 crop year to complete, followed by the September 2027 Grain Stocks + October 2027 WASDE). The look-ahead was reading data that will not be publicly knowable until October 2027 as if it was knowable on August 1 2026. This systematically inflated the signal’s in-sample HAC-t statistics by giving the backtest access to future information.
THE HONEST CAVEAT
The USDA_FAS_PSD table does not contain monthly WASDE revision vintages for US corn ending stocks , only one snapshot per marketing year reflecting the latest fetch date (which varies across bulk-refetch cycles, 2016-07 for pre-2015 data and 2025-07 for 2017-2022). The publication-lag model used in this patch is a DETERMINISTIC conservative-anchor approximation of actual WASDE publication timing, not true point-in-time vintage tracking. A more accurate point-in-time implementation would require pulling from USDA_WASDE_CELLS / USDA_WASDE_REPORTS historical vintages, which per the DATA_INVENTORY are only fresh from 2025+ (not historically filled historically per owner directive 2026-06-30).
THE REGIME MAP
The three US corn ending-stocks YoY regime states, forward returns and sample share
Behavior across the inverted YoY ending-stocks signal (CBOT corn benchmark). Positive composite reads YoY stocks DOWN (supply tightening, author-thesis-aligned bullish). Negative composite reads YoY stocks UP (supply loosening, bearish). The signal is publication-lag aware: each marketing year’s value anchors at October 1 of the following year, when September Grain Stocks and October WASDE have reconciled.
| State | Phase | Share | Fwd 60d | HAC t | Edge vs baseline | Last firings |
|---|---|---|---|---|---|---|
| Stocks Loosening TODAY | – | 35.0% (3162 d) | -4.92% | -5.21pp | May 2026, May 2022, Oct 2013 | |
| Stocks Neutral | 0 | 21.0% (1898 d) | -3.77% | -4.06pp | Mar 2026, Mar 2025, Mar 2022 | |
| Stocks Tightening | + | 44.1% (3984 d) | +6.47% | +6.18pp | May 2025, Dec 2017, Jun 2016 |
The historical pattern
Alert drafts
THE TRACK RECORD
State changes
| State | Start | End | Duration | Fwd 60d SPY |
|---|---|---|---|---|
| Negative | 10/23/2024 | 03/26/2025 | 106d | +4.92% |
| Neutral | 03/27/2025 | 05/23/2025 | 41d | +7.00% |
| Positive | 05/27/2025 | 03/11/2026 | 199d | +7.51% |
| Neutral | 03/12/2026 | 05/08/2026 | 41d | +10.98% |
| Negative | 05/11/2026 | 10/23/2026 | 116d | +3.96% |
Scroll inside the table for the full history. Forward 60-day SPY is measured from each run’s start date; a reader cannot trade off a start-date they only identify in hindsight, so this is a transparency log, not an alpha claim. Asterisked (*) returns are partial. The run is less than 60 trading days old. The full 60-day comparable fills in as more data arrives.
What this measures
The engine queries USDA Foreign Agricultural Service Production, Supply, and Distribution data for US corn Ending Stocks by marketing year. For each market year MY, computes year-over-year percent change against MY-1 ending stocks. Anchors each YoY value at `Timestamp(year=MY+1, month=10, day=1)` , the earliest date at which the final reconciled number is realistically known publicly (after September Grain Stocks quarterly + October WASDE revision). The anchored YoY series is interpolated to daily via a month-end-aware function, z-scored on a 1,260-trading-day rolling window with 60-day minimum, polarity-inverted (rising stocks YoY → negative signal), and tanh-bounded. Five-state machine: EXTREME_NEG below minus 0.5 (stocks building YoY, bearish for corn), MODERATE_NEG between minus 0.5 and minus 0.2, NORMAL between plus-or-minus 0.2, MODERATE_POS between plus 0.2 and plus 0.5, EXTREME_POS above plus 0.5 (stocks tight YoY, bullish for corn).
GO DEEPER
Want the full depth?
The full research brief adds methodology detail on the publication-lag awareness built into the signal construction (each marketing year’s value anchors at October 1 of the following year to avoid look-ahead), the year-over-year difference computation, and the rank-z-score normalization. Includes three historical case studies anchored to actual marketing-year balance resolutions, the three-regime state-conditional table, and the methodology for pairing with the Development Pace, Silking Pace, Condition WoW, and the Corn Cycle DNA playbook.
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Not investment advice · The analysis on this page is informational and educational. Signal readings, historical case figures, and empirical statistics are derived from publicly available data and are provided without warranty. Hypothetical performance results have inherent limitations, including the benefit of hindsight. Readers who intend to trade should consult a licensed investment professional and see the research brief for the full disclaimer.
Last refreshed Nov 02, 2026 11:46 AM ET