In the 2010 "Flash Crash," the U.S. stock market lost roughly a trillion dollars of value in minutes — then recovered most of it before the day was over.

On Black Monday — October 19, 1987 — the Dow fell 22.6% in a single day, still its worst one-day percentage drop ever. No single piece of news fully explains it.

The first great stock bubble burst three centuries ago. In 1720 shares of Britain’s South Sea Company shot from around £100 to nearly £1,000 in a matter of months, then collapsed back toward £100 by year-end — ruining thousands of investors.

Japanese stocks compounded at roughly 17% a year through the 1970s and nearly 29% a year through the 1980s — turning $10,000 in 1970 into about $610,000 by 1989. The bubble then burst so completely that the Nikkei 225 didn’t reclaim its December 1989 peak until February 2024, a 35-year round trip.