SPX sessions closed in negative gamma, with the net-gamma percentile under 20, on retail sales days

13 sessions · the archive filtered by the dealer book · all sessions · the calendar

13 of 1,122 sessions match. Of them 0% closed above the flip (archive 56%) and the mean open-to-close move was 0.85% (archive 0.59%).

Every row is a finished SPX session and links to its page, where the same numbers stand with the day's events and a free minute-by-minute replay. The filters are the closing measurements those pages print: the zero-gamma flip against the close and the open, the net-gamma percentile, how often the flip was crossed, and the calendar event the day carried. The shares above are counts over the matched days next to the same counts over the whole archive; a share that matches the archive is a base rate, not a pattern.

SessionCloseMoveFlipvs flipPctlCrossEvents
2026-04-217,063.60-0.78%7,091.0-27.4511Retail sales
2026-03-066,739.82-0.02%6,752.2-12.4518NFP, Retail sales
2025-09-166,607.10-0.26%6,608.4-1.31511Retail sales, Auctions
2025-08-156,450.35-0.30%6,455.7-5.4025Retail sales, Opex
2025-02-146,114.37-0.07%6,115.6-1.3513Retail sales, UMich
2025-01-165,938.27-0.33%5,946.5-8.21639Retail sales, Claims, EIA
2024-10-175,842.22-0.52%5,851.5-9.31513Retail sales, Claims, EIA
2024-04-155,061.25-1.99%5,097.1-35.856Retail sales
2023-08-154,437.62-0.78%4,451.1-13.51513Retail sales
2023-05-164,110.21-0.37%4,122.4-12.2024Retail sales, Fed
2023-01-183,927.50-1.98%3,959.2-31.7155PPI, Retail sales, VIX settlement, Auctions
2022-10-143,586.86-2.87%3,615.2-28.3155Retail sales, UMich
2022-09-153,902.26-0.71%3,923.0-20.8010Retail sales, Claims, EIA

Turn a filter into a rule

A count is where a question starts. The Lab takes a rule in plain words ("sell the 0DTE straddle at 10:00 on days that opened below the flip with the percentile under 20"), compiles it against every archived session and reports the out-of-sample verdict with day-clustered intervals. An assistant with the MCP server can page through the same archive with list_sessions and get_session.

Measurements are model output derived from public trade and quote data; they are approximations and can be wrong. Nothing here is investment advice; see the Terms.