1. An iterative drilling simulation method for enhanced economic decision making comprising: obtaining characteristics of a rock column in a formation to be drilled; specifying characteristics of at least one drilling rig system; and iteratively simulating the drilling of a well bore in the formation and producing an economic evaluation factor for each iteration of drilling simulation, wherein each iteration of drilling simulation is a function of the rock column and the characteristics of the at least one drilling rig system according to a prescribed drilling simulation model.