{"slug":"why-spreads-widen-at-the-open","qid":"mu_gap","label":"MU into July 7, 2026: prior regular-session close, opening print, overnight gap","post_title":"Why Are Spreads Wider at the Open? Real Data","post_url":"/blog/why-spreads-widen-at-the-open#q-mu_gap","columns":["prior_close","jul7_open","overnight_gap_pct"],"rows":[{"prior_close":984.31,"jul7_open":923.01,"overnight_gap_pct":-6.2}],"shape":"scalar","sql":"WITH prev AS (\n    SELECT argMax(toFloat64(close), window_start) AS prev_close\n    FROM global_markets.delayed_stocks_minute_aggs\n    WHERE ticker = 'MU'\n      AND window_start >= '2026-07-06 13:30:00'\n      AND window_start < '2026-07-06 20:00:00'\n),\nday AS (\n    SELECT argMin(toFloat64(open), window_start) AS day_open\n    FROM global_markets.delayed_stocks_minute_aggs\n    WHERE ticker = 'MU'\n      AND window_start >= '2026-07-07 13:30:00'\n      AND window_start < '2026-07-07 20:00:00'\n)\nSELECT round((SELECT prev_close FROM prev), 2) AS prior_close,\n       round((SELECT day_open FROM day), 2) AS jul7_open,\n       round(((SELECT day_open FROM day) - (SELECT prev_close FROM prev)) / (SELECT prev_close FROM prev) * 100, 1) AS overnight_gap_pct","computed_at":"2026-08-08T04:51:06.591015+00:00","elapsed":0.06166414}