The Stock Market Works by Day, but It Loves the Night (2018)
nytimes.com
nytimes.com
If you had bought the SPY at the last second of trading on each business day since 1993 and sold at the market open the next day — capturing all of the net after-hour gains — your cumulative price gain would be 571 percent.
On the other hand, if you had done the reverse, buying the E.T.F. at the first second of regular trading every morning at 9:30 a.m. and selling at the 4 p.m. close, you would be down 4.4 percent