Does Williams %R bounce actually work on SPY? We tested it
We ran Williams %R bounce on SPY through walk-forward testing and a 100-run random-entry gauntlet. 4 of 4 unseen periods positive. Beat 91 of 100 random-entry runs.
You gave up raw return for a higher win rate and a shallower drawdown. This setup is about timing and staying out of trouble, not beating the index.
Equity curve over Aug 2016 to Jul 2026. Hover any point for its value. Turn on buy and hold to compare.
The same rules, tested on 28 tickers. Edge held on 12. We ship it on those.
Show every ticker we tested
This strategy made money overall, turning a 35.55% total return on 31 trades. The ride was fairly steady, with a high 74.19% win rate and a modest worst drawdown of -7.25% that happened in early 2025. The entry timing is a major strength here, as your real entries outperformed 91% of random entry runs, meaning the signal to buy when Williams %R crosses above -90 while price is above the 200-day SMA is doing the heavy lifting. The edge was also consistent, showing up as profitable in all four walk-forward test periods, so the result is not just a lucky streak. The worst pain came from that single drawdown period in February and March 2025, but overall the losses were shallow and infrequent.
Every verdict on this page comes from the same process. How we test.
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