Oct 14 close Sign in

Mean reversion · daily rule · Crypto

Bollinger Reversion on Bitcoin

What the play says

Out since Jul 3, 2026at $62,544BTC since then +32.9%

Next move

Buys on a daily close below $81,050.

$81,050
−2.5% from the Oct 13 close of $83,095

Next check: the Oct 14, 2026 close

See every reason, for and against, in the Theory tester

BTC with the play, last two years

BTC20-day SMALower bandPlay inPlay out

Shading shows the play's call from the close that triggered it.

Growth of $10,000 since 2014

Bollinger ReversionBuy & hold

Log scale. After trading costs, with T-bill interest while out.

The record

The play against buying and holding BTC over exactly the same dates, after costs.

Play, since 2014Hold, since 2014Play, 5 yrsHold, 5 yrs
Annual return−5.3%+58.1%+0.1%+7.7%
Total return−48%+24,617%+1%+45%
Worst drawdown−80.0%−83.4%−54.9%−76.6%
Volatility39.0%65.9%30.6%51.1%
Sharpe ratio0.011.000.040.33
Time invested23%100%
Switches per year10.50

Every call, graded

Right on 76 of 126 closed calls (60%). In calls averaged −0.4%; out calls saw BTC move +18.1% on average.

CalledCallPriceUntilBTC movedResult
Jul 3, 2026OUT$62,544now+32.9%open
Jun 25, 2026IN$59,722Jul 3, 2026+4.7%✓ right
Jun 20, 2026OUT$64,240Jun 25, 2026−7.0%✓ right
May 22, 2026IN$75,488Jun 20, 2026−14.9%✕ wrong
Mar 2, 2026OUT$68,776May 22, 2026+9.8%✕ wrong
Jan 31, 2026IN$78,621Mar 2, 2026−12.5%✕ wrong
Dec 30, 2025OUT$88,430Jan 31, 2026−11.1%✓ right
Dec 15, 2025IN$86,420Dec 30, 2025+2.3%✓ right
Dec 2, 2025OUT$91,350Dec 15, 2025−5.4%✓ right
Nov 4, 2025IN$101,591Dec 2, 2025−10.1%✕ wrong
Sep 29, 2025OUT$114,400Nov 4, 2025−11.2%✓ right
Sep 25, 2025IN$109,049Sep 29, 2025+4.9%✓ right

An in call is right when the price rose before the next call; an out call is right when it fell. The latest 12 of 127 calls shown.

How the play works

  1. In on a close below the lower band (20-day average − 2 standard deviations).
  2. Out on a close above the 20-day average.

This runs against Bollinger's advice that tags of the bands are not signals. It is shown because so many traders use it.

The case against

Valeriy Zakamulin tested moving-average timing on up to 155 years of U.S. stock data and found no statistically significant edge in the second half of that record. The rules earned their keep in a few severe bear markets and lagged buy and hold for long stretches in between.

Read the skeptic's scoreboard

Free account

Know the moment the light flips on your stocks.

Follow your stocks and get an email with the analysis the evening a light flips. Member tools are free until January 1, 2027.