{"slug":"the-wash-sale-rule-and-options","qid":"window_sessions","label":"How many trading sessions fit inside a 61 day wash sale window","post_title":"Wash Sale Rule and Options: The 61-Day Window","post_url":"/blog/the-wash-sale-rule-and-options#q-window_sessions","columns":["month","last_session","sessions_in_window","calendar_days_in_window"],"rows":[{"month":"2024-01-01","last_session":"2024-01-31","sessions_in_window":42,"calendar_days_in_window":61},{"month":"2024-02-01","last_session":"2024-02-29","sessions_in_window":42,"calendar_days_in_window":61},{"month":"2024-03-01","last_session":"2024-03-28","sessions_in_window":43,"calendar_days_in_window":61},{"month":"2024-04-01","last_session":"2024-04-30","sessions_in_window":43,"calendar_days_in_window":61},{"month":"2024-05-01","last_session":"2024-05-31","sessions_in_window":41,"calendar_days_in_window":61},{"month":"2024-06-01","last_session":"2024-06-28","sessions_in_window":41,"calendar_days_in_window":61},{"month":"2024-07-01","last_session":"2024-07-31","sessions_in_window":44,"calendar_days_in_window":61},{"month":"2024-08-01","last_session":"2024-08-30","sessions_in_window":42,"calendar_days_in_window":61},{"month":"2024-09-01","last_session":"2024-09-30","sessions_in_window":42,"calendar_days_in_window":61},{"month":"2024-10-01","last_session":"2024-10-31","sessions_in_window":43,"calendar_days_in_window":61},{"month":"2024-11-01","last_session":"2024-11-29","sessions_in_window":41,"calendar_days_in_window":61},{"month":"2024-12-01","last_session":"2024-12-31","sessions_in_window":40,"calendar_days_in_window":61},{"month":"2025-01-01","last_session":"2025-01-31","sessions_in_window":39,"calendar_days_in_window":61},{"month":"2025-02-01","last_session":"2025-02-28","sessions_in_window":42,"calendar_days_in_window":61},{"month":"2025-03-01","last_session":"2025-03-31","sessions_in_window":42,"calendar_days_in_window":61},{"month":"2025-04-01","last_session":"2025-04-30","sessions_in_window":43,"calendar_days_in_window":61},{"month":"2025-05-01","last_session":"2025-05-30","sessions_in_window":41,"calendar_days_in_window":61},{"month":"2025-06-01","last_session":"2025-06-30","sessions_in_window":41,"calendar_days_in_window":61},{"month":"2025-07-01","last_session":"2025-07-31","sessions_in_window":43,"calendar_days_in_window":61},{"month":"2025-08-01","last_session":"2025-08-29","sessions_in_window":42,"calendar_days_in_window":61},{"month":"2025-09-01","last_session":"2025-09-30","sessions_in_window":43,"calendar_days_in_window":61},{"month":"2025-10-01","last_session":"2025-10-31","sessions_in_window":42,"calendar_days_in_window":61},{"month":"2025-11-01","last_session":"2025-11-28","sessions_in_window":41,"calendar_days_in_window":61},{"month":"2025-12-01","last_session":"2025-12-31","sessions_in_window":42,"calendar_days_in_window":61},{"month":"2026-01-01","last_session":"2026-01-30","sessions_in_window":40,"calendar_days_in_window":61},{"month":"2026-02-01","last_session":"2026-02-27","sessions_in_window":42,"calendar_days_in_window":61},{"month":"2026-03-01","last_session":"2026-03-31","sessions_in_window":43,"calendar_days_in_window":61},{"month":"2026-04-01","last_session":"2026-04-30","sessions_in_window":42,"calendar_days_in_window":61},{"month":"2026-05-01","last_session":"2026-05-29","sessions_in_window":41,"calendar_days_in_window":61},{"month":"2026-06-01","last_session":"2026-06-30","sessions_in_window":42,"calendar_days_in_window":61}],"shape":"series","sql":"WITH sessions AS\n(\n    SELECT DISTINCT date AS d\n    FROM global_markets.stocks_daily_aggs\n    WHERE ticker = 'SPY'\n      AND date >= '2023-11-01'\n),\nmonth_ends AS\n(\n    SELECT\n        toStartOfMonth(d) AS m,\n        max(d)            AS anchor\n    FROM sessions\n    WHERE d >= '2024-01-01'\n      AND d <  '2026-07-01'\n    GROUP BY m\n)\nSELECT\n    toString(me.m)                                            AS month,\n    toString(me.anchor)                                       AS last_session,\n    countIf(s.d >= me.anchor - 30 AND s.d <= me.anchor + 30)   AS sessions_in_window,\n    61                                                        AS calendar_days_in_window\nFROM month_ends AS me\nCROSS JOIN sessions AS s\nGROUP BY me.m, me.anchor\nORDER BY me.m","computed_at":"2026-08-13T15:39:29.048082+00:00","elapsed":0.002743233}