Oct 13 close Sign in

Mean reversion · daily rule · Energy & power

Bollinger Reversion on Capital Power

What the play says

Out since Sep 23, 2026at C$61.87CPX since then +4.6%

Next move

Buys on a daily close below C$58.47.

C$58.47
−9.7% from the Oct 13 close of C$64.74

Next check: the Oct 14, 2026 close

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

CPX with the play, last two years

CPX20-day SMALower bandPlay inPlay out

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

Growth of C$10,000 since 2009

Bollinger ReversionBuy & hold

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

The record

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

Play, since 2009Hold, since 2009Play, 5 yrsHold, 5 yrs
Annual return+6.0%+13.3%+3.1%+14.2%
Total return+168%+735%+16%+94%
Worst drawdown−37.9%−47.4%−18.3%−33.8%
Volatility14.0%23.4%12.6%25.5%
Sharpe ratio0.380.590.010.50
Time invested21%100%
Switches per year8.80

Every call, graded

Right on 97 of 150 closed calls (65%). In calls averaged +1.2%; out calls saw CPX move +2.3% on average.

CalledCallPriceUntilCPX movedResult
Sep 23, 2026OUTC$61.87now+4.6%open
Jul 28, 2026INC$67.40Sep 23, 2026−8.2%✕ wrong
May 7, 2026OUTC$64.77Jul 28, 2026+4.1%✕ wrong
Apr 29, 2026INC$61.09May 7, 2026+6.0%✓ right
Jan 26, 2026OUTC$58.00Apr 29, 2026+5.3%✕ wrong
Jan 16, 2026INC$55.45Jan 26, 2026+4.6%✓ right
Dec 4, 2025OUTC$59.74Jan 16, 2026−7.2%✓ right
Nov 6, 2025INC$65.07Dec 4, 2025−8.2%✕ wrong
Apr 17, 2025OUTC$44.20Nov 6, 2025+47.2%✕ wrong
Apr 4, 2025INC$41.49Apr 17, 2025+6.5%✓ right
Mar 21, 2025OUTC$45.25Apr 4, 2025−8.3%✓ right
Feb 27, 2025INC$46.80Mar 21, 2025−3.3%✕ wrong

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 151 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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