Bounce off the lower Bollinger band does not beat buy-and-hold on CPRT: -16.9 points a year over 32 years.
Findings derived from the full panel. Each carries its number and its denominator; the computations are reproducible with artifact 30497848a621.
Close crosses back above the lower band (20, 2σ) after piercing it → entry. Close reaches the 20-day mean → exit.
The verdict compares the strategy with buying and holding CPRT over the same window, with round-trip costs per asset class. “Out of sample” is walk-forward: the rule is fit on one stretch and judged on the next. A result that beats in the full sample but not out of it is overfit. Full methodology in the protocol. How we test.
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Finaxion Research (2026). Does Bounce off the lower Bollinger band work on CPRT?. Daily backtest 1962-01-01–2026-08-31, artifact 30497848a621. https://finaxion.app/en/research/bollinger-bounce/cprt
Not a recommendation. Past performance does not guarantee future results.