SledgeKey Backtests
Classic strategies, tested two ways
Every strategy here is backtested on survivorship-free, point-in-time data, with the companies that went bankrupt, were seized, or left the exchange kept in the test the whole way through. On three of the pages we run the same screen a second time on a survivor-only universe, the way most free tools quietly do, to put an exact number on the bias. Across our runs that number has been positive, zero and negative, which is the point: it depends on how a strategy's holdings left the market, and only the two-way test can tell you. Each page shows its full methodology. No account needed to read any of it.
Figures as of September 2026. Every number on the pages below comes from one run per page, with windows ending in September 2026. We refresh our published backtests once a quarter rather than every time the data moves, so the same screen run in the app on today's data can differ a little. Next refresh: January 2027. How we date and refresh these pages.
Rebalance Frequency
The Quality at a Fair Price screen run four times over the same ten years, changing only the rebalance schedule: annual, semi-annual, quarterly, monthly. Twice a year finished first at 12.33% a year, once a year finished last at 11.14%, and the Monte Carlo cones around all four results overlap almost completely.
As of Sep 2026
Midcap Value
P/E under 15 and a $2B–$20B market cap band, held from 2017 through 2026. The honest run trailed the index by 4.2 points a year, and here the bias runs against the strategy: a survivor-only backtester, blind to the fifteen holdings that were bought out or delisted, reports it 1.51 points a year worse than it was.
As of Sep 2026
The Magic Formula
Joel Greenblatt's cheap-and-high-return-on-capital screen from The Little Book That Beats the Market, run honestly from 2017 through 2026 with delisted companies kept in. It made 14.74% a year and trailed a plain S&P 500 index fund by about half a point; its twenty largest qualifying names never included one that later delisted, so the survivor-only run is identical.
As of Sep 2026
Piotroski-Style Financial Strength
A levels version of Joseph Piotroski's financial-strength checklist, bolted onto a price-to-book value anchor and run from 2017 through 2026. Kept honest it made 9.52% a year and trailed the index. A survivor-only universe pads that by 3.06 points a year it never earned, the largest overstatement in any of our runs.
As of Sep 2026
Quality at a Fair Price
Return on equity and operating margin above 15%, a P/E ceiling of 25 and positive free cash flow, run once a year from September 2016 to September 2026. It made 11.49% a year against 15.35% for the index. The screen was calmer: in the index's up months it gained 73% as much, and in its down months it lost 70% as much. In a strong decade for the index, that lower exposure kept it 3.86 points a year behind.
As of Sep 2026
Graham's Defensive Investor
Benjamin Graham's defensive investor rules, five absolute filters run once a year from September 2016 to September 2026. Kept honest it made 13.75% a year and trailed the index by 1.60 points. It stood level with the index at the end of 2023, seven years in, and the whole shortfall arrived in the two years and nine months after that.
As of Sep 2026
How these backtests are run
Every page discloses its complete configuration: every filter, threshold, weighting rule, rebalance schedule, and cost assumption. The universe is NYSE and NASDAQ operating companies (no SPACs, REITs, ETFs, or funds) built point-in-time, so eligibility at each rebalance reflects the companies actually listed on that date. In the honest runs, holdings that delist are booked out at their frozen last traded price. In the survivor-only runs, later-delisted companies are excluded from the universe entirely, which is what most free backtesting tools silently do.
When a strategy loses to the index, the page says so, and every analysis carries a caveats section listing what the result fails to establish.
Run this yourself
Every configuration on these pages is reproducible in the app. The free Starter plan screens all 5,000+ NYSE and NASDAQ companies across all 31 metrics and backtests two years of point-in-time data, with no credit card and no expiry. SledgeKey+ extends the same engine to the full ten years, adds Black-Scholes protective put hedging, a 5,000-path Monte Carlo projection, and a 9-section research PDF, for $22 a month or $220 a year.