FINAXIONResearch
Finaxion Research · Bounce off the lower Bollinger band · single stocks · Recomputed 2026-09-10

Does Bounce off the lower Bollinger band work on GOOGL?

Bounce off the lower Bollinger band does not beat buy-and-hold on GOOGL: -21.9 points a year over 22 years.

Total return
97.2%
Buy and hold
×136
CAGR
3.1%
Sharpe
0.02
Max drawdown
-43.5%
Trades
166
Out of sample
overfit
Years
22
1×10×100×151×20052007200920112013201520172019202120232025
StrategyGOOGL

Findings

  1. Bounce off the lower Bollinger band does not beat buy-and-hold on GOOGL: -21.9 points a year over 22 years.
  2. Against the S&P 500 over the same window: -8.1 points a year.
  3. Total return +97.2% versus ×136 for buy-and-hold, with 166 trades.
  4. The result does not hold out of sample: it is overfit.
  5. Maximum drawdown -43.5%.
  6. It beats in neither half of the history (split at 2015).
  7. It ranks #102 of 235 markets for this strategy by annual excess over the S&P 500.

Findings derived from the full panel. Each carries its number and its denominator; the computations are reproducible with artifact 30497848a621.

Exactly what was tested

Close crosses back above the lower band (20, 2σ) after piercing it → entry. Close reaches the 20-day mean → exit.

How to read it

The verdict compares the strategy with buying and holding GOOGL 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.

Open this backtest with its trades   Trades (CSV)

Every strategy on GOOGL → · Full page for Bounce off the lower Bollinger band →

How to cite

Finaxion Research (2026). Does Bounce off the lower Bollinger band work on GOOGL?. Daily backtest 1962-01-01–2026-08-31, artifact 30497848a621. https://finaxion.app/en/research/bollinger-bounce/googl

Not a recommendation. Past performance does not guarantee future results.