Trying to model behavior of portfolio in response to shock event(s) during regular trading hours (not overnight). Why shock event? Because in case of shock stops may not be much of a help. Thus effect on multiple positions will be more significant, so it is important to know possible scenarios/correlations So, it is 11:00 AM Eastern time and ... Case1: Significant terrorist act ES-down bond-down $-down gold-flat/or up Case2: Sudden selloff in equities ("bad news from Asia" or "1987") ES-down bond-down $-down gold-flat/or up This might be an oversimplification. Still, some scenarios are more likely than others, brainstorming this topic appears to be a valuable exercise.