Oct 13 close Sign in

Calendar · daily rule · Software & devices

Halloween Indicator on CrowdStrike

What the play says

Out since Apr 30, 2026at $111.44CRWD since then +134.4%

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

CRWD with the play, last two years

CRWDPlay inPlay out

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

Growth of $10,000 since 2019

Halloween IndicatorBuy & hold

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

The record

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

Play, since 2019Hold, since 2019Play, 5 yrsHold, 5 yrs
Annual return+14.0%+45.4%+2.6%+31.2%
Total return+161%+1,447%+13%+286%
Worst drawdown−64.0%−67.7%−59.7%−67.7%
Volatility39.3%56.2%37.1%52.6%
Sharpe ratio0.460.900.150.71
Time invested47%100%
Switches per year1.90

Every call, graded

Right on 6 of 14 closed calls (43%). In calls averaged +20.1%; out calls saw CRWD move +23.0% on average.

CalledCallPriceUntilCRWD movedResult
Apr 30, 2026OUT$111.44now+134.4%open
Oct 31, 2025IN$135.75Apr 30, 2026−17.9%✕ wrong
Apr 30, 2025OUT$107.22Oct 31, 2025+26.6%✕ wrong
Oct 31, 2024IN$74.22Apr 30, 2025+44.5%✓ right
Apr 30, 2024OUT$73.14Oct 31, 2024+1.5%✕ wrong
Oct 31, 2023IN$44.19Apr 30, 2024+65.5%✓ right
Apr 28, 2023OUT$30.01Oct 31, 2023+47.2%✕ wrong
Oct 31, 2022IN$40.30Apr 28, 2023−25.5%✕ wrong
Apr 29, 2022OUT$49.69Oct 31, 2022−18.9%✓ right
Oct 29, 2021IN$70.45Apr 29, 2022−29.5%✕ wrong
Apr 30, 2021OUT$52.13Oct 29, 2021+35.1%✕ wrong
Oct 30, 2020IN$30.96Apr 30, 2021+68.4%✓ 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 15 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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