Oct 13 close Sign in

Calendar · daily rule · Energy & power

Halloween Indicator on Hydro One

What the play says

Out since Apr 30, 2026at C$57.61H since then −10.7%

Next move

Stays out until the close on Oct 30, 2026, when the calendar says it buys. No price can change that.

Oct 30
17 days from the Oct 13 close

Next change: the Oct 30, 2026 close

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

H with the play, last two years

HPlay inPlay out

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

Growth of C$10,000 since 2015

Halloween IndicatorBuy & hold

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

The record

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

Play, since 2015Hold, since 2015Play, 5 yrsHold, 5 yrs
Annual return+10.2%+11.7%+18.3%+14.5%
Total return+188%+234%+131%+96%
Worst drawdown−27.7%−27.7%−9.1%−17.1%
Volatility12.5%15.9%10.0%15.0%
Sharpe ratio0.660.641.350.72
Time invested50%100%
Switches per year1.90

Every call, graded

Right on 15 of 21 closed calls (71%). In calls averaged +9.4%; out calls saw H move +4.2% on average.

CalledCallPriceUntilH movedResult
Apr 30, 2026OUTC$57.61now−10.7%open
Oct 31, 2025INC$50.46Apr 30, 2026+14.2%✓ right
Apr 30, 2025OUTC$51.04Oct 31, 2025−1.1%✓ right
Oct 31, 2024INC$42.56Apr 30, 2025+19.9%✓ right
Apr 30, 2024OUTC$36.08Oct 31, 2024+18.0%✕ wrong
Oct 31, 2023INC$33.15Apr 30, 2024+8.8%✓ right
Apr 28, 2023OUTC$36.00Oct 31, 2023−7.9%✓ right
Oct 31, 2022INC$30.53Apr 28, 2023+17.9%✓ right
Apr 29, 2022OUTC$30.55Oct 31, 2022−0.1%✓ right
Oct 29, 2021INC$25.58Apr 29, 2022+19.4%✓ right
Apr 30, 2021OUTC$25.06Oct 29, 2021+2.1%✕ wrong
Oct 30, 2020INC$24.33Apr 30, 2021+3.0%✓ 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 22 calls shown.

How the play works

  1. In at the close on the last trading day of October.
  2. Out at the close on the last trading day of April.

The research used market indexes. Applying it to one stock assumes the season carries over.

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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