The Momentum Portfolio
A simple, fully mechanical strategy: rank every US stock above $1B market cap by its 12-month price momentum, skipping the most recent month, hold the top 25 equal-weight, and re-rank at every month-end. No forecasts, no discretion. We tested it point-in-time on three separate windows back to 2009 — including two we never touched while designing it. It beat the S&P 500 in 2016–2026 and 2009–2012, and lost to it in 2012–2016 (9.7% vs 11.4%/yr). We publish the loss next to the wins — the honest caveats are below, right next to the results.
This month’s basket
Loading the current top-25…
Check against your portfolio
See which basket names you already hold and which of your holdings are outside the basket this month. Informational only — this compares tickers, it does not tell you to buy or sell anything.
The backtest — three independent windows
Same rules applied point-in-time: universe membership and market cap use only data knowable at each rebalance (annual filings with a 91-day lag, and that day’s price). The 2012-2016 and 2009-2012 windows were run after the strategy was fixed on 2016-2026 data — a true out-of-sample check. The strategy won 2009-2012 and lost 2012-2016: momentum rode the 2013-2015 mid-cap biotech run-up straight into the late-2015 crash. One win, one loss out-of-sample — that is the record, and we show both.
Methodology — and what this test can and cannot claim
- Signal: 12M-1M price momentum — the close one month before the rebalance divided by the close thirteen months before, minus one. The most recent month is skipped because short-term returns tend to reverse (the standard academic convention). Nothing else: no earnings, no scores, no opinions.
- Universe: US-listed stocks with market cap ≥ $1B at the rebalance date, mega caps and mid caps competing in one pool. In testing, letting the whole spectrum compete beat restricting to either group alone.
- Portfolio: the top 25 by momentum, equal weight, re-ranked every month-end. Typically 5-10 names change per month, not the whole basket. Wider baskets (25) survived out-of-sample; concentrated ones (top 5-10) looked better in-sample and failed out-of-sample, so we don’t use them.
- What we tried and rejected, in the open: per-stock trailing stop-losses (whipsawed, made results worse), market regime filters — 200-day trend, partial exposure, volatility-index tiers (each helped one window, hurt another; none passed both), quality-fundamental gates on top of momentum (diluted returns at monthly cadence). The bankruptcy check was the one defensive test that passed: in nine real collapses (2020-2023), momentum turned deeply negative 3-12 months before the end, so the monthly re-rank had already rotated out of every one of them.
- Where this page came from: our original test asked whether ranking stocks by fundamentals beats the market. Honest answer: it didn’t (top-quintile 11.3%/yr vs SPY 13.5% in the mega-cap universe, 2016-2026). We published nothing and kept iterating; the momentum finding above is what survived every check we could throw at it.