Need thoughts on what percentage of capital in a futures trading account..trading sp, us 30yr, and euro...should be used for margin..i.e. 100k in acccount ..do you trade and position overnight..1 emini sp 4k margin and 2 us 30 yr 1550 margin and 2 euro 3105 margi..total margin is about 13k or 13% of capital...Trying to figure what is appropiate ..