{"_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/1148026","as_of":"2026-10-08T16:48:25.454596Z","docs":"https://api.pdata.world/docs","cite_as":"According to pdata.world (tracking Polymarket): \"S&P 500 (SPX) Opens Up or Down on October 8?\" — 0% as of 2026-10-08 UTC. https://pdata.world/events/polymarket/1148026","source_url":"https://polymarket.com/event/spx-opens-up-or-down-on-october-8-2026"},"source":"polymarket","id":"1148026","ticker":"spx-opens-up-or-down-on-october-8-2026","slug":"spx-opens-up-or-down-on-october-8-2026","title":"S&P 500 (SPX) Opens Up or Down on October 8?","description":"This market will resolve to \"Up\" if the official S&P 500 Index open price for S&P 500 (SPX) on October 8 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 8 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":"2026-10-07T12:01:04Z","end_date":"2026-10-08T20:00:00Z","closed_time":null,"volume":4476.1477859999995,"volume_24hr":4476.1477859999995,"volume_24h_change":null,"normalized_vol_24hr":30.21329689025879,"normalized_volume":16.05827522277832,"liquidity":18134.75292,"open_interest":3089.48626,"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":-0.5445000000000001,"top_outcome_volume_24h_change":4476.1477859999995,"updated_at":"2026-10-08T16:45:35.700949Z","fetched_at":"2026-10-08T16:45:35.700949Z","added_at":"2026-10-07T12:23:50.310171Z","url":"https://polymarket.com/event/spx-opens-up-or-down-on-october-8-2026","chart_24h":[0.0,0.0,0.0,0.0,23.0,23.0,63.0,63.0,63.0,103.0,105.589373,105.589373,105.589373,106.808884,106.808884,112.28833499999999,317.288335,397.288335,492.793561,558.793561,658.793561,818.063104,836.063104,1311.6064379999998,1311.6064379999998,1511.424195,2179.283986,3065.5939860000003,4457.377786,4457.377786,4476.1477859999995],"kind":"live","mutually_exclusive":false,"markets_total":1,"markets":[{"source":"polymarket","id":"5404186","event_id":"1148026","slug":"spx-opens-up-or-down-on-october-8-2026","question":"S&P 500 (SPX) Opens Up or Down on October 8?","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 8 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 8 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":"2026-10-07T12:01:04Z","end_date":"2026-10-08T20:00:00Z","closed_time":null,"result":null,"volume":4476.1477859999995,"volume_24hr":4476.1477859999995,"prob_24h_change":-0.5445000000000001,"volume_24h_change":4476.1477859999995,"normalized_vol_24hr":32.13102722167969,"normalized_volume":20.73497772216797,"liquidity":15634.55292,"categories":["Finance"],"countries":[],"updated_at":"2026-10-08T16:45:35.973531Z","fetched_at":"2026-10-08T16:45:35.973531Z","added_at":"2026-10-07T12:23:50.420403Z","url":"https://polymarket.com/event/spx-opens-up-or-down-on-october-8-2026/spx-opens-up-or-down-on-october-8-2026","event_title":"S&P 500 (SPX) Opens Up or Down on October 8?","chart_24h":[0.545,0.545,0.655,0.525,0.515,0.5,0.505,0.545,0.545,0.545,0.545,0.485,0.525,0.355,0.15,0.115,0.13,0.105,0.06,0.015,0.015,0.0165,0.0125,0.0005,0.0005,0.0005,0.0005]}]}