SPX sessions closed in negative gamma, with the net-gamma percentile 20 to 50

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

225 of 1,122 sessions match. Of them 0% closed above the flip (archive 56%) and the mean open-to-close move was 0.58% (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
2026-09-307,651.51-0.55%7,700.1-48.6455PCE, GDP, Fed, VIX settlement, EIA
2026-09-287,683.49-0.30%7,693.7-10.22514Retail sales
2026-09-147,620.56+0.27%7,626.6-6.1356
2026-09-107,591.60-0.02%7,597.6-6.04014PPI, Claims, EIA, Auctions
2026-09-087,673.17-0.43%7,687.6-14.42021Auctions
2026-08-287,711.50-0.34%7,720.5-9.0209UMich
2026-08-247,653.24-0.03%7,657.1-3.84512
2026-08-127,748.52-0.17%7,750.6-2.03522CPI, VIX settlement, EIA, Auctions
2026-08-117,727.62-0.45%7,736.1-8.4209Auctions
2026-08-107,752.95-0.04%7,754.9-1.93013
2026-07-287,428.00+0.19%7,432.2-4.23015Confidence, Auctions
2026-07-177,458.16+0.12%7,471.9-13.82510Housing, UMich, Opex
2026-07-167,533.67-0.32%7,542.1-8.4357Retail sales, Claims, EIA
2026-07-017,483.35+0.14%7,497.6-14.23015VIX settlement, ISM, Housing, EIA
2026-06-257,355.80-0.86%7,365.2-9.43019PCE, Housing, GDP, Claims, EIA, Auctions
2026-06-247,358.75-0.22%7,374.9-16.2458Housing, VIX settlement, EIA, Auctions, Fed
2026-06-177,420.70-1.31%7,478.2-57.4359Retail sales, VIX settlement, EIA, FOMC
2026-06-157,553.95+0.24%7,558.2-4.2303
2026-06-107,267.52-1.08%7,317.1-49.6353CPI, VIX settlement, EIA, Auctions
2026-05-227,473.35-0.15%7,483.6-10.3255UMich
2026-05-197,354.17-0.17%7,364.8-10.72022VIX settlement
2026-05-157,407.72-0.30%7,429.9-22.12016Opex
2026-04-237,108.32-0.16%7,113.8-5.5356Claims, EIA
2026-03-266,477.72-0.97%6,521.3-43.6304Claims, EIA, Auctions
2026-03-256,591.77-0.45%6,598.7-6.92531VIX settlement, EIA, Auctions
2026-03-246,556.00+0.24%6,567.2-11.23524Auctions
2026-03-236,582.06-0.30%6,606.4-24.4459Housing
2026-03-206,506.42-1.18%6,534.8-28.43518Opex
2026-03-176,716.85-0.28%6,724.8-8.03013Auctions
2026-03-166,699.55+0.12%6,700.8-1.33021
2026-03-126,673.29-0.66%6,694.2-20.93026Housing, Claims, EIA, Auctions
2026-03-106,781.42-0.20%6,804.9-23.52017Auctions
2026-02-136,836.35+0.01%6,852.3-15.94018CPI
2026-02-126,832.81-1.87%6,874.9-42.1351Claims, EIA, Auctions
2026-02-116,942.22-0.68%6,949.1-6.83539NFP, VIX settlement, EIA, Auctions
2026-02-106,941.12-0.44%6,962.3-21.23023Retail sales, Auctions
2026-02-096,964.56+0.81%6,965.0-0.4305
2026-02-056,799.37-0.34%6,813.2-13.83014Claims, JOLTS, EIA
2026-02-046,882.81-0.55%6,888.1-5.24523Refunding, VIX settlement, ISM, EIA, Fed
2026-02-026,976.55+0.71%6,979.1-2.5405ISM, Fed, Refunding
2026-01-276,978.77+0.21%6,979.9-1.1308Housing, Confidence, Auctions
2026-01-266,950.70+0.37%6,956.9-6.2211Housing, Auctions
2026-01-236,915.51+0.13%6,916.0-0.53225UMich
2026-01-226,912.90-0.12%6,918.1-5.2329PCE, GDP, Claims, EIA
2026-01-156,944.02-0.30%6,959.1-15.12625Claims, EIA
2026-01-076,921.37-0.33%6,944.7-23.33711Housing, VIX settlement, JOLTS, EIA
2026-01-056,901.52+0.05%6,907.8-6.2267
2025-12-126,827.49-0.91%6,837.8-10.3323UMich
2025-12-056,870.36-0.03%6,871.3-0.94729PCE
2025-11-186,617.56-0.33%6,637.1-19.64520Housing
2025-11-176,672.66-0.52%6,698.4-25.74014Housing
2025-11-146,733.27+0.99%6,746.0-12.73014UMich
2025-11-136,737.27-1.20%6,768.1-30.8254EIA, Auctions
2025-11-056,796.75+0.35%6,812.5-15.8252Refunding, VIX settlement, ISM, EIA
2025-10-246,791.30+0.16%6,798.8-7.5251CPI, UMich
2025-10-216,735.02+0.00%6,740.2-5.23021
2025-10-166,629.25-0.95%6,649.4-20.1205EIA
2025-10-156,670.77-0.21%6,673.6-2.8309VIX settlement, Fed
2025-09-236,657.12-0.54%6,672.5-15.32517Fed, Auctions
2025-09-186,631.82+0.15%6,635.4-3.52522Claims, EIA
2025-09-106,532.62-0.07%6,534.1-1.42012PPI, VIX settlement, EIA, Auctions
2025-08-216,369.95+0.05%6,371.7-1.83038Claims, EIA
2025-08-196,411.52-0.53%6,418.8-7.3307Housing
2025-08-116,373.37-0.28%6,386.5-13.13023
2025-08-016,238.35-0.55%6,241.8-3.53711NFP, ISM, Housing
2025-07-306,362.67-0.20%6,368.9-6.22112GDP, Refunding, VIX settlement, EIA, FOMC
2025-07-116,259.27+0.10%6,260.3-1.13714UMich
2025-06-175,982.67-0.48%6,003.0-20.4359Retail sales
2025-06-135,976.75-0.39%5,993.7-17.02017UMich, Fed
2025-06-116,022.71-0.40%6,035.1-12.44012CPI, VIX settlement, EIA, Auctions
2025-06-045,971.50-0.16%5,980.2-8.74021ISM, EIA, Fed
2025-05-235,802.87+0.50%5,809.9-7.03514Housing, UMich
2025-05-135,886.65+0.71%5,890.1-3.4251CPI
2025-05-085,664.05-0.13%5,690.0-25.9259Claims, EIA, Auctions
2025-04-235,377.07-0.77%5,390.9-13.8305Housing, VIX settlement, EIA, Auctions, Fed
2025-04-175,282.85-0.33%5,299.9-17.04025Housing, Claims, EIA, Fed, Opex
2025-04-165,274.90-1.27%5,286.8-11.94013Retail sales, VIX settlement, EIA, Auctions, Fed
2025-04-155,396.91-0.33%5,407.1-10.12019
2025-04-145,405.10-0.87%5,418.6-13.42011
2025-03-265,712.15-1.12%5,733.0-20.8253Housing, VIX settlement, EIA, Auctions
2025-03-185,614.57-0.60%5,616.3-1.72036Housing, VIX settlement, Auctions
2025-03-135,521.45-1.11%5,542.5-21.03012PPI, Claims, EIA, Fed, Auctions
2025-03-115,572.65-0.60%5,586.1-13.54025JOLTS, Auctions
2025-03-105,614.39-1.34%5,629.6-15.2402
2025-03-065,737.42-0.50%5,750.9-13.5406Claims, EIA
2025-03-045,778.45-0.48%5,797.6-19.23516
2025-03-035,849.17-2.04%5,908.7-59.52025ISM, Housing
2025-02-275,862.32-2.05%5,930.5-68.23023Housing, GDP, Claims, EIA
2025-02-265,956.42-0.15%5,969.4-13.0405Housing, VIX settlement, EIA, Auctions
2025-02-255,955.17-0.53%5,956.1-0.92519Confidence, Auctions
2025-01-296,038.10-0.31%6,040.5-2.44527VIX settlement, EIA, FOMC
2025-01-246,101.27-0.30%6,105.5-4.2267UMich
2025-01-226,086.39+0.18%6,089.9-3.5261VIX settlement, Auctions
2025-01-105,826.27-0.78%5,838.5-12.34214NFP, UMich, EIA
2025-01-075,908.07-1.50%5,937.6-29.6323JOLTS, Auctions
2024-12-305,907.25+0.14%5,918.0-10.7394
2024-12-205,933.15+1.63%5,944.5-11.44214PCE, Opex
2024-12-195,867.92-0.91%5,900.4-32.43216GDP, Claims, EIA
2024-12-185,872.81-2.88%6,008.0-135.2321Housing, VIX settlement, EIA, FOMC
2024-11-275,997.97-0.24%5,999.1-1.14525PCE, Housing, GDP, Claims, VIX settlement, EIA, Auctions
2024-11-135,986.47-0.07%5,992.7-6.22015CPI, VIX settlement
2024-11-125,984.54-0.34%5,987.8-3.3259
2024-11-085,996.20+0.24%5,996.8-0.6405UMich
2024-11-045,713.45-0.30%5,722.5-9.03523Housing, Auctions
2024-11-015,729.05-0.04%5,744.6-15.62011NFP, ISM, Housing
2024-10-235,796.62-0.64%5,796.7-0.12517VIX settlement, EIA, Auctions
2024-10-015,707.97-0.75%5,712.3-4.32018ISM, JOLTS, Housing
2024-09-255,721.32-0.33%5,724.0-2.74514Housing, VIX settlement, EIA, Auctions
2024-09-195,714.34+0.04%5,716.0-1.74512Claims, EIA
2024-09-185,618.30-0.34%5,636.8-18.53021Housing, VIX settlement, EIA, FOMC
2024-09-045,520.47+0.15%5,523.2-2.73526Housing, VIX settlement, JOLTS
2024-08-295,592.71-0.29%5,620.4-27.7206GDP, Claims, EIA, Auctions
2024-08-285,592.71-0.59%5,593.7-1.04523VIX settlement, EIA, Auctions
2024-08-265,616.92-0.49%5,618.4-1.43017Housing
2024-08-205,596.97-0.16%5,598.5-1.62519
2024-08-065,238.87+0.62%5,272.0-33.1358Auctions
2024-07-295,464.52-0.13%5,470.3-5.83727Refunding
2024-07-195,505.47-0.67%5,515.8-10.43212Opex
2024-07-185,545.79-0.97%5,559.6-13.8377Claims, EIA
2024-07-175,589.10-0.40%5,596.6-7.53212Housing, VIX settlement, EIA, Auctions
2024-07-095,577.12-0.09%5,578.7-1.53232Fed, Auctions
2024-06-125,420.71+0.02%5,424.6-3.9357CPI, VIX settlement, EIA, FOMC
2024-05-165,297.22-0.27%5,309.4-12.2253Housing, Claims, EIA
2024-04-265,100.26+0.46%5,103.1-2.8406PCE, UMich
2024-04-175,022.95-0.98%5,036.8-13.9308VIX settlement, EIA, Auctions
2024-04-165,052.19-0.25%5,061.1-8.94037Housing
2024-04-085,202.66-0.11%5,209.0-6.32541
2024-04-045,148.32-1.98%5,220.4-72.12511Claims, EIA
2024-04-035,212.30+0.31%5,217.9-5.6258VIX settlement, ISM, EIA
2024-03-255,219.07-0.00%5,225.9-6.84046Housing
2024-03-225,234.17-0.13%5,238.9-4.73027UMich
2024-03-215,242.55-0.17%5,249.7-7.22519Claims, EIA
2024-03-185,150.15-0.23%5,162.0-11.9457
2024-03-155,115.77-0.23%5,118.6-2.83025Opex
2024-03-065,104.87-0.14%5,108.2-3.33019Fed, VIX settlement, JOLTS, EIA
2024-03-055,078.42-0.61%5,082.2-3.8302Housing, ISM
2024-02-235,089.57-0.27%5,093.0-3.53028UMich
2024-01-054,696.42+0.11%4,698.8-2.43522NFP, Housing
2023-12-224,755.32-0.08%4,758.3-3.02613PCE, Housing, UMich
2023-11-224,556.65-0.05%4,556.7-0.03517Housing, Claims, VIX settlement, EIA
2023-11-154,503.47-0.13%4,509.0-5.52527PPI, Retail sales, VIX settlement, EIA
2023-11-034,359.15+0.40%4,360.9-1.8303NFP, ISM
2023-10-274,116.84-0.85%4,126.9-10.12518PCE, UMich
2023-10-254,186.77-0.99%4,199.0-12.2256Housing, VIX settlement, EIA, Auctions
2023-10-234,217.89+0.18%4,232.4-14.52010
2023-10-194,278.11-1.04%4,304.1-26.02014Claims, EIA
2023-10-134,327.77-0.97%4,334.8-7.0407UMich
2023-10-124,349.45-0.67%4,356.6-7.14018CPI, Claims, EIA, Auctions
2023-10-104,357.87+0.41%4,364.2-6.34020Auctions
2023-09-294,287.70-0.92%4,302.0-14.34518PCE
2023-09-264,274.47-0.81%4,284.3-9.83014Housing, Confidence
2023-09-204,401.82-1.15%4,439.9-38.13518VIX settlement, EIA, FOMC
2023-09-124,462.47-0.19%4,470.8-8.34017Auctions
2023-09-084,458.17+0.06%4,459.0-0.84015UMich, Fed
2023-09-054,496.90-0.33%4,505.4-8.54523Housing
2023-08-244,376.61-1.71%4,409.1-32.5452Housing, Claims, EIA
2023-08-174,373.20-1.08%4,401.0-27.8309Claims, EIA
2023-08-044,477.02-0.88%4,515.8-38.8203NFP
2023-08-034,501.19+0.13%4,505.7-4.53523Housing, Claims, ISM, EIA
2023-07-254,567.82+0.33%4,568.6-0.8474Confidence, Auctions
2023-07-214,536.25-0.28%4,544.7-8.53228Opex
2023-07-124,471.84-0.12%4,474.6-2.83715CPI, VIX settlement, EIA, Auctions
2023-07-054,446.82+0.22%4,446.9-0.0267Housing, VIX settlement, EIA
2023-06-214,365.75-0.17%4,372.1-6.33024Fed, VIX settlement, Auctions
2023-06-204,389.45-0.02%4,390.4-0.93012Housing
2023-06-054,274.77-0.28%4,282.5-7.74015Housing, ISM
2023-05-304,206.22-0.50%4,207.8-1.63531Confidence
2023-05-234,146.99-0.66%4,169.1-22.13510Housing
2023-05-224,192.09-0.05%4,196.8-4.73514
2023-05-034,091.15-0.85%4,119.2-28.02515Refunding, VIX settlement, ISM, EIA, FOMC
2023-04-204,129.42+0.10%4,131.5-2.1305Claims, EIA
2023-04-044,099.47-0.72%4,100.8-1.44510Housing, JOLTS
2023-03-273,976.32-0.48%3,985.2-8.92521
2023-03-233,948.67-0.54%3,969.4-20.73013Housing, Claims, EIA
2023-03-173,915.85-0.89%3,919.9-4.12521Opex
2023-03-133,856.47+0.85%3,874.5-18.14516Halts
2023-03-103,861.60-1.16%3,887.1-25.5256NFP, UMich
2023-03-093,917.82-2.06%3,985.2-67.4457Claims, EIA, Fed, Auctions
2023-02-273,981.87-0.53%3,992.2-10.3407Housing
2023-02-223,989.80-0.33%3,993.8-4.02018VIX settlement, Auctions
2023-02-213,997.21-1.12%4,013.5-16.3306
2023-02-164,092.07-0.21%4,117.7-25.62516Housing, PPI, Claims, EIA
2023-02-094,081.49-1.74%4,111.0-29.5259Claims, EIA, Auctions, Fed
2023-02-084,119.07-0.61%4,124.8-5.73011VIX settlement, EIA, Auctions
2023-02-034,136.10+0.08%4,147.0-10.9302NFP, ISM
2023-01-304,017.60-0.68%4,036.0-18.42522Refunding
2023-01-053,807.95-0.58%3,815.7-7.84012Claims, ISM, EIA
2022-12-273,828.47-0.40%3,833.6-5.14014Confidence
2022-12-153,895.91-1.35%3,903.8-7.9218Retail sales, Claims, EIA
2022-12-143,997.90-0.60%4,006.1-8.24210VIX settlement, EIA, FOMC
2022-12-073,934.77+0.00%3,936.7-2.04738VIX settlement, EIA
2022-12-063,942.12-1.37%3,956.2-14.1323
2022-11-163,960.30-0.40%3,967.2-6.93024Retail sales, VIX settlement, EIA, Auctions
2022-11-153,991.67-0.71%4,001.3-9.72017PPI, Fed
2022-11-143,957.77-0.44%3,990.4-32.6309
2022-11-023,760.95-2.27%3,829.5-68.62511Refunding, VIX settlement, EIA, FOMC
2022-11-013,857.77-1.35%3,862.1-4.34015ISM, JOLTS, Housing
2022-10-313,871.72-0.10%3,877.0-5.34526Refunding
2022-10-073,641.52-1.59%3,663.1-21.6453NFP
2022-10-063,743.92-0.68%3,761.5-17.62526GDP, Claims, EIA

Showing the first 200 of 225; the JSON carries all of them.

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.