March contracts on the Dow Jones Industrial Average traded 522 points lower to 11,584 as of 11:30 a.m. Eastern.
Futures contract don't move in complete lockstep to the underlying indexes, but by comparison, the Dow industrials fell 382 points on Sept. 20, 2001, just days after the terrorist attack on the Twin Towers, and by 387 points on Aug. 9, 2007, shortly after the recent credit crunch first emerged.