The best day for the markets, in terms of the largest single-day point gain for the Dow Jones Industrial Average, was October 13th, 2008.
It happened when the Dow closed up 936 points in response to seemingly positive news about the handling of the ongoing financial crisis. The market would fall much further however before the next uptrend began, on March 9, 2009.
In percentage terms, the biggest gain for the Dow came on March 15, 1933, when the index shot up over 15% (8.26 points) in response to Franklin D. Roosevelt's (FDR) Emergency Banking Act.
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