Abstract: Navigation devices in rental vehicles are used to assist in predicting the probability of when each car will be returned to the car rental company. The probability of each car being returned is based upon is location relative to the return facility, direction of travel, and whether the navigation device is currently routed to the return facility. It is not necessary to predict accurately when a specific car will be returned, although one could implement it that way. Rather, this is primarily a statistical prediction over a large number of vehicles that will inform the car rental company how many vehicles of each type will be returned at a given time.