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

Does Bounce off the lower Bollinger band work on BLK?

Bounce off the lower Bollinger band does not beat buy-and-hold on BLK: -18.7 points a year over 27 years.

Total return
46.8%
Buy and hold
×138
CAGR
1.4%
Sharpe
-0.06
Max drawdown
-52.7%
Trades
184
Out of sample
overfit
Years
27
1×10×100×138×20002002200420062008201020122014201620182020202220242026
StrategyBLK

Findings

  1. Bounce off the lower Bollinger band does not beat buy-and-hold on BLK: -18.7 points a year over 27 years.
  2. Against the S&P 500 over the same window: -7.3 points a year.
  3. Total return +46.8% versus ×138 for buy-and-hold, with 184 trades.
  4. The result does not hold out of sample: it is overfit.
  5. Maximum drawdown -52.7%.
  6. It beats in neither half of the history (split at 2013).
  7. It ranks #72 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 BLK 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 BLK → · Full page for Bounce off the lower Bollinger band →

How to cite

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

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