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It should have been the bull market's 11th birthday on Monday: Since March 9, 2009, stocks have notched record-setting gains without a market crash; as recently as Feb. 19—less than three weeks ago—the S&P 500 closed at an all-time high of 3386.15.
Instead, the stock market recorded its worst day since the depths of the financial crisis in December 2008, as a Saudi-prompted crash in oil prices combined with spiraling fears that coronavirus quarantines could freeze the global economy. A swift selloff forced a rare halt in all stock trading just moments after the market opened Monday, as a 7% decline in stocks triggered what's known as "circuit breakers" on the exchanges.
