{"_meta":{"attribution":"Data aggregated by pdata.world (https://pdata.world) from 8 prediction-market venues; CC BY 4.0; source data © each venue.","canonical_url":"https://pdata.world/events/polymarket/1271598","as_of":"2026-10-29T18:37:17.565398Z","docs":"https://api.pdata.world/docs","cite_as":"According to pdata.world (tracking Polymarket): \"S&P 500 (SPX) Opens Up or Down on October 29?\" — 0% as of 2026-10-29 UTC. https://pdata.world/events/polymarket/1271598","source_url":"https://polymarket.com/event/spx-opens-up-or-down-on-october-29-2026"},"source":"polymarket","id":"1271598","ticker":"spx-opens-up-or-down-on-october-29-2026","slug":"spx-opens-up-or-down-on-october-29-2026","title":"S&P 500 (SPX) Opens Up or Down on October 29?","description":"This market will resolve to \"Up\" if the official S&P 500 Index open price for S&P 500 (SPX) on October 29 is higher than the official S&P 500 Index closing price for SPX on the most recent prior trading day.\n\nThis market will resolve to \"Down\" if the official S&P 500 Index open price for S&P 500 (SPX) on October 29 is lower than the official S&P 500 Index closing price for SPX on the most recent prior trading day.\n\nE.g., ordinarily, a market on Monday would refer to the previous Friday for its most recent closing price, unless that Friday were a market holiday, in which case it would refer to Thursday, or the next most recent trading day.\n\nIf the two prices are exactly equal, this market will resolve 50-50. Note that all figures will be rounded to the nearest cent using standard rounding.\n\nIf SPX does not trade at all during the regular session, the market will resolve 50-50.\n\nIf either of the relevant days are shortened (for example, due to a market holiday schedule), the official open/close price published by S&P 500 Index for that shortened session will still be used for resolution.\n\nIf the previous trading day has no official closing price (for example, due to a trading halt into the market close, system issue, delisting, or other disruption), the market will use the last valid on-exchange trade price of the regular session as the effective closing price.\n\nThe resolution source for this market is the Wall Street Journal, specifically the Open/Close values published by the WSJ under \"Historical Prices\".\n\nUS: https://www.wsj.com/market-data/stocks\nEMEA: https://www.wsj.com/market-data/stocks/emea\nASIA: https://www.wsj.com/market-data/stocks/asia","image":"https://polymarket-upload.s3.us-east-2.amazonaws.com/s-and-p-500-1e40af6979.png","icon":"https://polymarket-upload.s3.us-east-2.amazonaws.com/s-and-p-500-1e40af6979.png","active":true,"closed":false,"start_date":"2026-10-28T12:01:00Z","end_date":"2026-10-29T20:00:00Z","closed_time":null,"volume":4233.329286,"volume_24hr":4233.329286,"volume_24h_change":null,"normalized_vol_24hr":27.327016830444336,"normalized_volume":15.836429595947266,"liquidity":6260.30336,"open_interest":3061.589286,"categories":["Finance"],"tags":[{"id":"102683","slug":"spx","label":"SPX"},{"id":"102127","slug":"up-or-down","label":"Up or Down"},{"id":"102281","slug":"daily","label":"Daily"},{"id":"102682","slug":"indicies","label":"Indicies"},{"id":"120","slug":"finance","label":"Finance"},{"id":"102169","slug":"hide-from-new","label":"Hide From New"}],"synthetic":false,"is_group":false,"group_key":null,"parent_event_id":null,"probability":null,"spread":null,"top_outcome":"","top_outcome_probability":0.0005,"top_outcome_prob_24h_change":-0.3145,"top_outcome_volume_24h_change":4233.329286,"updated_at":"2026-10-29T17:53:17.937037Z","fetched_at":"2026-10-29T17:53:17.937037Z","added_at":"2026-10-28T12:23:50.566456Z","url":"https://polymarket.com/event/spx-opens-up-or-down-on-october-29-2026","chart_24h":[0.0,20.0,25.0,25.0,35.269999999999996,35.269999999999996,35.269999999999996,35.269999999999996,35.269999999999996,35.269999999999996,341.98,351.98,582.805911,582.805911,1092.905911,1102.905911,1102.905911,1108.0659110000001,2211.648286,3812.799286,4233.329286,4233.329286,4233.329286,4233.329286],"kind":"live","mutually_exclusive":false,"markets_total":1,"markets":[{"source":"polymarket","id":"6339668","event_id":"1271598","slug":"spx-opens-up-or-down-on-october-29-2026","question":"S&P 500 (SPX) Opens Up or Down on October 29?","group_item_title":null,"description":"This market will resolve to \"Up\" if the official S&P 500 Index open price for S&P 500 (SPX) on October 29 is higher than the official S&P 500 Index closing price for SPX on the most recent prior trading day.\n\nThis market will resolve to \"Down\" if the official S&P 500 Index open price for S&P 500 (SPX) on October 29 is lower than the official S&P 500 Index closing price for SPX on the most recent prior trading day.\n\nE.g., ordinarily, a market on Monday would refer to the previous Friday for its most recent closing price, unless that Friday were a market holiday, in which case it would refer to Thursday, or the next most recent trading day.\n\nIf the two prices are exactly equal, this market will resolve 50-50. Note that all figures will be rounded to the nearest cent using standard rounding.\n\nIf SPX does not trade at all during the regular session, the market will resolve 50-50.\n\nIf either of the relevant days are shortened (for example, due to a market holiday schedule), the official open/close price published by S&P 500 Index for that shortened session will still be used for resolution.\n\nIf the previous trading day has no official closing price (for example, due to a trading halt into the market close, system issue, delisting, or other disruption), the market will use the last valid on-exchange trade price of the regular session as the effective closing price.\n\nThe resolution source for this market is the Wall Street Journal, specifically the Open/Close values published by the WSJ under \"Historical Prices\".\n\nUS: https://www.wsj.com/market-data/stocks\nEMEA: https://www.wsj.com/market-data/stocks/emea\nASIA: https://www.wsj.com/market-data/stocks/asia","image":"https://polymarket-upload.s3.us-east-2.amazonaws.com/s-and-p-500-1e40af6979.png","icon":"https://polymarket-upload.s3.us-east-2.amazonaws.com/s-and-p-500-1e40af6979.png","outcomes":["Up","Down"],"outcome_prices":[0.0005,0.9995],"probability":0.0005,"spread":0.001,"active":true,"closed":false,"start_date":"2026-10-28T12:01:00Z","end_date":"2026-10-29T20:00:00Z","closed_time":null,"result":null,"volume":4233.329286,"volume_24hr":4233.329286,"prob_24h_change":-0.3145,"volume_24h_change":4233.329286,"normalized_vol_24hr":30.347763061523438,"normalized_volume":20.46082305908203,"liquidity":21250.27717,"categories":["Finance"],"countries":[],"updated_at":"2026-10-29T14:49:31.861741Z","fetched_at":"2026-10-29T14:49:31.861741Z","added_at":"2026-10-28T12:23:50.774147Z","url":"https://polymarket.com/event/spx-opens-up-or-down-on-october-29-2026/spx-opens-up-or-down-on-october-29-2026","event_title":"S&P 500 (SPX) Opens Up or Down on October 29?","chart_24h":[0.315,0.335,0.335,0.13,0.125,0.195,0.24,0.125,0.115,0.115,0.165,0.2,0.13,0.09,0.1,0.275,0.165,0.18,0.055,0.0105,0.0005,0.0005]}]}