From GROK ... Greatest SPY overnight gap down March 9, 2020: ~19.05 points (274.23 close to 255.18 open). We're currently -21 Are we making history ? Breaking records ?! (that was a 7.45% overnight drop)
Fair enough. From GROK ... Greatest SPY overnight drop in percentage: September 17, 2001: ~8.22% (109.20 to 100.23). October 15, 2008: ~7.06% (90.00 to 83.65). March 9, 2020: ~6.95% (274.23 to 255.18). October 27, 1997: ~6.87% (97.35 to 90.66). Still room to go. Only down ~3%