FINAXIONResearch
Finaxion Research · The Turtles: 55-day breakout · single stocks · Recomputed 2026-09-10

Does the Turtles: 55-day breakout work on ALGN?

The Turtles: 55-day breakout does not beat buy-and-hold on ALGN: -5.3 points a year over 26 years.

Total return
165.3%
Buy and hold
846.9%
CAGR
3.9%
Sharpe
0.16
Max drawdown
-68.8%
Trades
96
Out of sample
overfit
Years
26
0.1×1×10×43×2002200420062008201020122014201620182020202220242026
StrategyALGN

Findings

  1. The Turtles: 55-day breakout does not beat buy-and-hold on ALGN: -5.3 points a year over 26 years.
  2. Against the S&P 500 over the same window: -5.0 points a year.
  3. Total return +165.3% versus +846.9% for buy-and-hold, with 96 trades.
  4. The result does not hold out of sample: it is overfit.
  5. Maximum drawdown -68.8%.
  6. It beats in neither half of the history (split at 2013).
  7. It ranks #73 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 0712690e8935.

Exactly what was tested

Close above the prior 55-day high → entry. Close below the prior 20-day low → exit (original System 2). No pyramiding or ATR sizing: we test the signal alone.

How to read it

The verdict compares the strategy with buying and holding ALGN 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 ALGN → · Full page for The Turtles: 55-day breakout →

How to cite

Finaxion Research (2026). Does the Turtles: 55-day breakout work on ALGN?. Daily backtest 1962-01-01–2026-08-31, artifact 0712690e8935. https://finaxion.app/en/research/donchian-55-breakout/algn

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