This field holds the link distance. As with free flow speed, data is entered separately for each directional link, so different distances can be entered for each direction. The user can enter any distance, and a running time will be calculated, unless the free flow speed is greater than 45 mph and the distance less than one mile. For some combinations of distance and free flow speed, the HCM recommends that the arterial class be reevaluated. TRAFFIX™ will generate a warning consistent with these recommendations but will proceed with calculations.