Oct 13 close Sign in

Mean reversion · daily rule · Industrials & materials

Bollinger Reversion on Stantec

What the play says

Out since Sep 22, 2026at C$99.94STN since then −3.6%

Next move

Buys on a daily close below C$93.34.

C$93.34
−3.1% from the Oct 13 close of C$96.33

Next check: the Oct 14, 2026 close

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

STN with the play, last two years

STN20-day SMALower bandPlay inPlay out

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

Growth of C$10,000 since 2005

Bollinger ReversionBuy & hold

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

The record

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

Play, since 2005Hold, since 2005Play, 5 yrsHold, 5 yrs
Annual return+4.4%+14.2%+2.4%+10.3%
Total return+155%+1,690%+13%+63%
Worst drawdown−41.4%−58.1%−33.5%−40.4%
Volatility16.0%28.4%13.1%24.3%
Sharpe ratio0.240.55−0.040.37
Time invested22%100%
Switches per year8.50

Every call, graded

Right on 110 of 184 closed calls (60%). In calls averaged +0.9%; out calls saw STN move +3.3% on average.

CalledCallPriceUntilSTN movedResult
Sep 22, 2026OUTC$99.94now−3.6%open
Sep 1, 2026INC$99.57Sep 22, 2026+0.4%✓ right
Jul 27, 2026OUTC$99.37Sep 1, 2026+0.2%✕ wrong
Jul 23, 2026INC$93.75Jul 27, 2026+6.0%✓ right
Jul 2, 2026OUTC$98.94Jul 23, 2026−5.2%✓ right
May 8, 2026INC$118.98Jul 2, 2026−16.8%✕ wrong
Feb 26, 2026OUTC$129.41May 8, 2026−8.1%✓ right
Feb 11, 2026INC$133.06Feb 26, 2026−2.7%✕ wrong
Dec 23, 2025OUTC$130.66Feb 11, 2026+1.8%✕ wrong
Nov 4, 2025INC$150.69Dec 23, 2025−13.3%✕ wrong
Aug 21, 2025OUTC$148.91Nov 4, 2025+1.2%✕ wrong
Aug 14, 2025INC$145.30Aug 21, 2025+2.5%✓ 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 185 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

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