Discover an idea, test it, and understand the evidence. Follow a strategy, see its upcoming trades, and verify the result afterward.
Every claim here is tested against the average hold of the same symbol for the same number of days, not against making money, because most of what looks seasonal is the stock going up. Nothing on this page is recomputed: every figure comes from a live endpoint, the same one its own page reads.
Scan the calendar
Every rule of the fixed calendar grid on every symbol, ordered by excess per year over holding the same symbol for the same length.
Check an idea
Bring a seasonal claim of your own, any date window, weekday, week or month, and see whether it beats the average hold of the same symbol for the same number of days.
Explore a symbol
One symbol's seasonality, charted: its average path through the year, its weekdays, days of the month and month-ends, and a heatmap of them.
Follow strategies
Seven named rules on SPY, with their evidence, what they did this year, their next entry and exit, and a forward record.
Two claims, checked live
The strongest example today, by excess per year
SPY, Monday open to Tuesday open
The shortest weekday hold this page can check: one session, every week on record.
- Excess / year
- +2.38%
- Positive years
- 15 of 26
- Latest 4Y
- +0.14%
Against holding SPY for the same number of sessions, gross.
Open on CheckA well-known claim
SPY, The Halloween effect
The folk claim that stocks turn upward once October ends. Named for the calendar date it starts on, not for a mechanism a fixed-length test can see.
- Excess / year
- +0.12%
- Positive years
- 16 of 26
- Latest 4Y
- +1.88%
Against holding SPY for the same number of sessions, gross.
Open on CheckStrategies this week
Today- Turn of the monthin a position
In since the open of Wednesday, Sep 30; exit at the open of Tuesday, Oct 6.
SPY at the open. Returns are gross, before your costs. Size is yours to decide.
Why these numbers can be trusted
- Every result is tested against an ordinary hold of the same length, not against zero.
- Every figure stops at the research cutoff; what a rule did since is shown beside it, never mixed in.
- A strategy’s rule was fixed by a study before it was measured here, and has not moved since.
- Every figure has a definition: read them in the glossary.