The escalating coronavirus emergency Thursday sent stocks to their worst losses since the Black Monday crash of 1987, extending a sell-off that has now wiped out most of Wall Street's big run-up since President Donald Trump's election.
The S&P 500 plummeted 9.5%, for a total drop of 26.7% from its all-time high, set just last month. That puts it way past the 20% threshold to make this a bear market, snapping an unprecedented, nearly 11-year bull-market run. The Dow Jones Industrial Average sank 10% for its worst day since a nearly 23% drop on Oct. 19, 1987.