The Thesis
Dual-momentum is one of the more durable systematic ideas in equity investing: rank a defined universe by 60-day return, hold the strongest trending names, and exit when the trend breaks. The logic is straightforward — price momentum tends to persist over intermediate horizons, and a hard exit rule prevents riding losers into the ground.
The Headmars implementation runs across a 24-stock universe spanning mega-cap tech (AAPL, MSFT, NVDA, GOOGL), financials (JPM, BAC, V, MA), healthcare (JNJ, UNH, PFE, ABBV), consumer staples and discretionary (PG, KO, WMT, COST, MCD, NKE, HD), and energy/industrials (XOM, CVX, CAT, HON, DIS). It is a deliberately blue-chip sandbox — liquid names with deep price history.
Backtest Headline
Over 451 days the strategy compounded to +23.5% total return (12.52% CAGR), ending with a simulated equity of $12,349.63 on a $10,000 starting account. The Sharpe ratio came in at 0.95, and maximum drawdown reached 15.67% — acceptable for a momentum strategy that can get caught flat-footed during reversals.
The win rate of 28.79% across 136 trades is worth pausing on. That figure is not unusual for trend-following; these strategies make money by letting winners run far past the average loss, not by being right most of the time. Turnover of 2,638% annualised, however, signals active rotation — at scale, transaction costs would need careful modelling.
Walk-Forward Validation: Where It Gets Interesting
The four-fold walk-forward tells a more nuanced story:
| Fold | Period | Return | Sharpe | Max DD |
|---|---|---|---|---|
| 1 | Aug 2024 – Jan 2025 | +5.85% | 1.23 | 3.92% |
| 2 | Jan 2025 – Jul 2025 | −7.31% | −1.05 | 17.15% |
| 3 | Jul 2025 – Dec 2025 | +25.59% | 3.32 | 4.04% |
| 4 | Dec 2025 – May 2026 | +13.34% | 2.15 | 7.43% |
Three of four folds were profitable, and the most recent out-of-sample period (Fold 4) posted the strongest risk-adjusted result in the set — a Sharpe of 2.15 on +13.34%. That is an encouraging tail.
Fold 2, however, was brutal: a 17.15% peak-to-trough drawdown and a negative Sharpe. A momentum strategy bleeding in early-to-mid 2025 is consistent with the kind of sharp sector rotations and macro cross-currents that punish trend-followers. The strategy had no structural defence against it.
The probabilistic Sharpe ratio (PSR) of 0.893 and deflated Sharpe ratio (DSR) of 0.476 reflect the six parameter trials run during development. A DSR below 0.5 means there is less than even odds the observed Sharpe is genuine after correcting for selection bias — the validation framework correctly flagged this as a fail.
Recent Activity: Sitting on Cash
The strategy has been fully in cash since at least 2 July, executing zero trades across six consecutive daily runs. This is the exit-on-trend-break rule working as designed — when no name in the universe clears the 60-day momentum threshold cleanly enough to trigger an entry, the strategy waits. Whether that patience will be rewarded or represents a missed window depends entirely on what happens next to the trend signals.
Strengths and Risks
Strengths: The concept is well-grounded in academic literature. The recent Fold 4 out-of-sample performance is genuinely encouraging. The cash-holding discipline prevents forced trades when conditions are unfavourable.
Risks: The DSR failure is a real flag — with six trials and a moderate Sharpe, there is meaningful probability the edge is partly illusory. High turnover will compress live returns relative to paper results. Fold 2's drawdown demonstrates the strategy has no momentum-crash protection built in.
Dual-momentum remains a strategy to watch, not yet one to deploy at full conviction. The current cash posture gives it a clean slate for the next trend cycle.