Descending Meter

Cars have meters that drivers reset whenever they want. These meters count in ascending way. They are good to tell us how many miles we drive from point A to point B. But they can not help us calculating how many miles remaining for us to reach our destination. We need meters that work in a descending way to do so. For instance, I am traveling from Washington D.C. to Chicago, IL, where the distance is 699 Miles. My car meter would tell me how many miles had I passed, as I am continue driving. But, it would not be able to tell me how many miles are remaining for me to arrive Chicago. I have to do the calculation in my mind. Thus, my idea is to add a descending meter to cars. Having such accessories in his/her car, traveler from Washington D.C. to Chicago would set the meter on 699 before he/she moves. Then, it would be easy for her/him to know how many miles are remaining before reaching the destination.

art h 06/22/2014
My navigation tells me how many miles left and the estimated time of arrival. 2012 Taurus sho.