Research

Calendar effects people ask about, each tested on every year of history against simply holding the same symbol for the same number of sessions. Every figure is gross, and each page shows the weak years beside the strong ones. Read how these pages are computed first.

• The FOMC announcement day on SPY

  Has SPY done better on Federal Reserve announcement days than an ordinary day?

  From 2000 to 2025, this rule did better than holding SPY for the same number of sessions in 14 of 26 years.

• October 31 on SPY: 15 sessions from Halloween

  Has SPY done better in the 15 sessions from October 31 than in any 15 sessions?

  From 2000 to 2025, this rule did better than holding SPY for the same number of sessions in 16 of 26 years.

• The turn of the month on SPY

  Has SPY done better around the turn of the month than in ordinary sessions?

  From 2000 to 2025, this rule did better than holding SPY for the same number of sessions in 15 of 26 years.