Here's a look at the Dow's 10 worst days since 1899:
By percent decline:-- Oct. 19, 1987: 22.6 percent, or 508 points
-- Oct. 28, 1929: 12.8 percent, or 38.33 points
-- Oct. 29, 1929: 11.7 percent, or 30.57 points
-- Nov. 6, 1929: 9.9 percent, or 25.55 points
-- Dec. 18, 1899: 8.7 percent, or 5.57 points
-- Aug. 12, 1932: 8.4 percent, or 5.79 points
-- March 14, 1907: 8.3 percent, or 6.89 points
-- Oct. 26, 1987: 8 percent, or 156.83 points
-- Oct. 15, 2008: 7.9 percent, or 733.08 points
-- July 21, 1933: 7.8 percent, or 7.55 points
By points:
-- Sept. 29, 2008: 777.68 points, or 7 percent
-- Oct. 15, 2008: 733.08 points, or 7.9 percent
-- Sept. 17, 2001: 684.81 points, or 7.1 percent
-- Dec. 1, 2008: 679.95 points, or 7.7 percent
-- Oct. 9, 2008: 678.92 points, or 7.3 percent
-- Aug. 8, 2011: 634.76 points, or 5.6 percent
-- April 14, 2000: 617.78 points, or 5.7 percent
-- Oct. 27, 1997: 554.26 points, or 7.2 percent
-- Oct. 22, 2008: 514.45 points, or 5.7 percent
-- Aug. 4, 2011: 512.61 points, or 4.3 percent
-- Aug. 31, 1998: 512.61 points, or 6.4 percent
Source: Dow Jones Indexes, a division of CME Group Inc.