Momentum FactorSystematic strategy construction and out-of-sample analysis
A long-only momentum strategy on US large-cap equities with a profitability filter and market regime overlay. 254 months of out-of-sample data. Quarterly TTM fundamentals with availability lag. Full drawdown, rolling return, and crisis period analysis.
I. Strategy Specification
Universe
US domestic common stocks, market cap > $5B
Signal
9-month total return, skip most recent month (9-1)
No 5-year window has ever produced a negative return. The worst 5-year annualized return was +2.7%. The strategy beat the S&P 500 in 88% of rolling 5-year periods.
V. Crisis Period Analysis
Crisis
Period
Strategy
S&P 500
Alpha
MA200 Cash
GFC (full)
2007-07–2009-03
+19.3%
-40.0%
+59.3%
17/21 mo
GFC (peak-trough)
2007-10–2009-02
-2.9%
-48.5%
+45.6%
16/17 mo
Flash Crash
2010-04–2010-08
-9.7%
-3.8%
-5.8%
4/5 mo
Debt Ceiling
2011-05–2011-10
-9.6%
-7.3%
-2.3%
3/6 mo
China/Oil
2015-06–2016-02
-5.4%
-0.2%
-5.3%
5/9 mo
Q4 2018
2018-09–2018-12
-19.2%
-7.2%
-12.0%
3/4 mo
COVID (3mo)
2020-01–2020-03
-4.9%
-9.7%
+4.8%
2/3 mo
COVID (6mo)
2020-01–2020-06
+7.5%
+1.4%
+6.1%
3/6 mo
Mom Crash 2021
2021-01–2021-12
+3.0%
+21.6%
-18.6%
No
2022 Bear
2022-01–2022-10
-1.0%
-9.6%
+8.6%
8/10 mo
2025 Tariffs
2025-01–2025-04
-14.4%
-2.1%
-12.3%
2/4 mo
The MA200 filter excels in prolonged downtrends (GFC, 2022 bear) but cannot protect against factor rotations where the broad market rises while momentum underperforms (2021). Fast crashes (Q4 2018) occur before the filter triggers. These are known structural limitations.
VI. Drawdown Analysis
All drawdowns exceeding −10%
Start
Trough
Recovery
Depth
Decline
Recovery
2005-02
2005-03
2005-05
-11.2%
1mo
2mo
2006-04
2006-07
2006-12
-12.6%
3mo
5mo
2011-04
2011-07
2012-08
-12.1%
3mo
13mo
2018-09
2019-08
2020-07
-21.6%
11mo
11mo
2021-11
2023-09
2024-02
-33.1%
22mo
5mo
2024-11
2025-02
2025-12
-19.0%
3mo
10mo
The worst drawdown (−33.1% for the deepest) was driven by the 2021 momentum crash followed by the 2022 bear market. The regime filter mitigated the market-wide decline but could not prevent the momentum-specific losses.
VII. Regime Filter Impact
Growth of $100,000 — with and without MA200
The MA200 filter reduces maximum drawdown from -65.0% to -33.1% while maintaining comparable CAGR. The cost is delayed re-entry after market bottoms, visible in the 2009 and 2023 underperformance streaks.
VIII. Rebalance Frequency Sensitivity
Frequency
CAGR
Alpha
Sharpe
MaxDD
Vol
$100K →
Monthly
+16.5%
+8.1%
0.76
-33.1%
17.9%
$2.56M
Quarterly
+15.6%
+7.2%
0.69
-35.6%
18.3%
$2.16M
Annual
+8.7%
+0.3%
0.34
-48.9%
16.5%
$581,494
Annual rebalance reduces CAGR by 7.9pp, eliminating nearly all alpha. Momentum is a fast-decaying signal. Monthly rebalance is required to capture the premium before it fades. Quarterly rebalance is an acceptable compromise with ~1pp CAGR drag and lower transaction costs.
IX. Rejected Modifications
Modification
Sharpe Δ
Reason
Inverse volatility weighting
−0.02
Underweights highest-momentum names
Momentum threshold > 5%
+0.00
Redundant in >$5B universe
ROIC > median filter
−0.06
Removes capital-intensive momentum winners; unstable across sub-periods
ROIC > 75th percentile
−0.04
Sharpe drops from 1.11 to 0.43 between sub-periods
Top 10 concentration
−0.06
Higher volatility without proportional return increase
Top 30 diversification
−0.03
Dilutes momentum signal
12-month lookback (with MA200)
−0.12
Stale signal, higher drawdowns
6-month lookback (with MA200)
−0.04
Signal too noisy for regime overlay
X. Known Risks and Limitations
Momentum crashes
Factor rotations where momentum underperforms the broad market (2021: +3% vs S&P +22%). The MA200 filter cannot protect against this — it only triggers on market-wide downtrends.
Sector concentration
Momentum naturally concentrates in leading sectors. In 2024–2025, this meant heavy AI/tech exposure. A sector shock would be amplified.
Transaction costs
Not modelled. Monthly rebalance of 20 large-cap stocks ≈ 5–10 trades/month. Estimated annual drag: 1–2%.
Taxes
Monthly rebalance generates short-term capital gains. After-tax CAGR may be 3–5pp lower.
Regime filter lag
MA200 is late at turning points. Fast crashes (Q4 2018) occur before the filter triggers. Recoveries (2009, 2023) see delayed re-entry.
Capacity
20 stocks >$5B investable up to ~$50M without significant market impact.
Recent outliers
2024 (+73%) is an extreme outlier. Do not extrapolate.
Survivorship
Sharadar includes 12,151 delisted stocks. Delisted names with incomplete price data may introduce residual bias.
XI. Methodology
Data source
Sharadar / Nasdaq Data Link
Fundamentals
Quarterly TTM (sf1_quarterly_ttm.parquet)
Availability lag
avail_ym field: 2 months after quarter end
Prices
Daily adjusted close incl. dividends
MA200
200 trading day simple moving average on S&P 500 close