Oct 13 close Sign in

Calendar · daily rule · Micro caps

Halloween Indicator on Ocean Power Technologies

What the play says

Out since Apr 30, 2026at $0.360OPTT since then +100.0%

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

OPTT with the play, last two years

OPTTPlay inPlay out

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

Growth of $10,000 since 2007

Halloween IndicatorBuy & hold

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

The record

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

Play, since 2007Hold, since 2007Play, 5 yrsHold, 5 yrs
Annual return−25.1%−35.2%−14.6%−19.5%
Total return−100%−100%−54%−66%
Worst drawdown−99.8%−100.0%−85.3%−98.2%
Volatility75.6%1,445.4%93.3%2,844.1%
Sharpe ratio−0.040.490.220.96
Time invested48%100%
Switches per year2.00

Every call, graded

Right on 19 of 39 closed calls (49%). In calls averaged −14.2%; out calls saw OPTT move −2.0% on average.

CalledCallPriceUntilOPTT movedResult
Apr 30, 2026OUT$0.360now+100.0%open
Oct 31, 2025IN$0.510Apr 30, 2026−29.4%✕ wrong
Apr 30, 2025OUT$0.410Oct 31, 2025+24.4%✕ wrong
Oct 31, 2024IN$0.150Apr 30, 2025+173.3%✓ right
Apr 30, 2024OUT$0.190Oct 31, 2024−21.1%✓ right
Oct 31, 2023IN$0.300Apr 30, 2024−36.7%✕ wrong
Apr 28, 2023OUT$0.510Oct 31, 2023−41.2%✓ right
Oct 31, 2022IN$0.730Apr 28, 2023−30.1%✕ wrong
Apr 29, 2022OUT$1.06Oct 31, 2022−31.1%✓ right
Oct 29, 2021IN$2.13Apr 29, 2022−50.2%✕ wrong
Apr 30, 2021OUT$2.51Oct 29, 2021−15.1%✓ right
Oct 30, 2020IN$1.69Apr 30, 2021+48.5%✓ 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 40 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.

Read the skeptic's scoreboard

Free account

Know the moment the light flips on your stocks.

Follow your stocks and get an email with the analysis the evening a light flips. Member tools are free until January 1, 2027.