If one trades one contract, what is the absolute maximum loss a single trader could have? I suppose it's not limited to the $6500 initial margin. Would it be the total cost of the contract, that is 5 x the Down Jones industrial Average Index at that given moment, i.e. if the Dow Jones is at 12,430 the total contract size in dollars is 5 x this = $62,150 ? Is this last amount the absolute maximum a single trader trading one contract could be liable for in the worst case scenario that the Dow goes to zero? Does anybody have the statistic of what is the maximum downturn or upturn that the dow has done in say one single hour ever? Ok, stupid questions I guess for some, but I was filling in the futures agreements with my broker I just thought I'd make sure of what I'm getting myself into. Thanks to anyone who replies even if only the first part of the question.