Which 1989 crash occurred when the U.S. stock market plunged after computerized trading and program selling intensified a brief panic?

The Friday the 13th mini-crash was the 1989 U.S. stock-market plunge intensified by computerized trading and program selling.

On Friday, October 13, 1989, the Dow Jones Industrial Average fell 190.58 points, or 6.91%. The immediate trigger was news that a leveraged buyout of United Airlines’ parent company had failed. Investors feared that the failure signaled broader problems in highly leveraged corporate finance, and selling accelerated through computerized trading strategies.

The decline was severe but short-lived compared with the 1987 crash. The episode became known as the Friday the 13th mini-crash because it occurred on that calendar date and was much smaller than Black Monday two years earlier. It also renewed debate about program trading, market liquidity, and safeguards against rapid declines.

This event is sometimes confused with the Flash Crash of May 6, 2010. The 1989 episode involved a failed buyout and a one-day market shock, while the 2010 event was a rapid intraday collapse and recovery.