Oct 13 close Sign in

Mean reversion · daily rule · Crypto miners

Bollinger Reversion on Bitdeer Technologies

What the play says

Out since Aug 20, 2026at $10.43BTDR since then −11.7%

Next move

Buys on a daily close below $8.35.

$8.35
−9.4% from the Oct 13 close of $9.21

Next check: the Oct 14, 2026 close

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

BTDR with the play, last two years

BTDR20-day SMALower bandPlay inPlay out

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

Growth of $10,000 since 2021

Bollinger ReversionBuy & hold

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

The record

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

Play, since 2021Hold, since 2021Play, 5 yrsHold, 5 yrs
Annual return−16.7%−1.2%−17.1%−1.5%
Total return−61%−6%−61%−7%
Worst drawdown−76.0%−79.5%−76.0%−79.5%
Volatility51.5%101.3%52.2%102.6%
Sharpe ratio−0.160.45−0.160.45
Time invested20%100%
Switches per year5.10

Every call, graded

Right on 11 of 26 closed calls (42%). In calls averaged −6.1%; out calls saw BTDR move +18.7% on average.

CalledCallPriceUntilBTDR movedResult
Aug 20, 2026OUT$10.43now−11.7%open
Jul 2, 2026IN$13.85Aug 20, 2026−24.7%✕ wrong
Mar 16, 2026OUT$8.20Jul 2, 2026+68.9%✕ wrong
Feb 12, 2026IN$10.37Mar 16, 2026−20.9%✕ wrong
Dec 9, 2025OUT$12.22Feb 12, 2026−15.1%✓ right
Nov 10, 2025IN$17.65Dec 9, 2025−30.8%✕ wrong
Sep 9, 2025OUT$13.85Nov 10, 2025+27.4%✕ wrong
Sep 4, 2025IN$12.01Sep 9, 2025+15.3%✓ right
Jul 2, 2025OUT$13.08Sep 4, 2025−8.2%✓ right
Jun 18, 2025IN$11.79Jul 2, 2025+10.9%✓ right
Apr 22, 2025OUT$9.38Jun 18, 2025+25.7%✕ wrong
Mar 31, 2025IN$8.83Apr 22, 2025+6.2%✓ 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 27 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.

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