three trillion http://www.businessinsider.com/vehicle-miles-driven-2013-2 http://www.businessinsider.com/vehicle-miles-driven-2013-2 http://www.businessinsider.com/vehicle-miles-driven-2013-2 http://www.businessinsider.com/vehicle-miles-driven-2013-2 http://www.businessinsider.com/vehicle-miles-driven-2013-2 http://www.businessinsider.com/vehicle-miles-driven-2013-2 http://www.businessinsider.com/vehicle-miles-driven-2013-2 http://www.businessinsider.com/vehicle-miles-driven-2013-2 http://www.businessinsider.com/vehicle-miles-driven-2013-2 http://www.businessinsider.com/vehicle-miles-driven-2013-2 http://www.businessinsider.com/vehicle-miles-driven-2013-2 http://www.businessinsider.com/vehicle-miles-driven-2013-2 http://www.businessinsider.com/vehicle-miles-driven-2013-2 http://www.businessinsider.com/vehicle-miles-driven-2013-2 http://www.businessinsider.com/vehicle-miles-driven-2013-2 http://www.businessinsider.com/vehicle-miles-driven-2013-2 http://www.businessinsider.com/vehicle-miles-driven-2013-2 http://www.businessinsider.com/vehicle-miles-driven-2013-2 http://www.businessinsider.com/vehicle-miles-driven-2013-2 http://www.businessinsider.com/vehicle-miles-driven-2013-2 http://www.businessinsider.com/vehicle-miles-driven-2013-2 http://www.businessinsider.com/vehicle-miles-driven-2013-2 http://www.businessinsider.com/vehicle-miles-driven-2013-2 they are driving less miles per year http://www.businessinsider.com/vehicle-miles-driven-2013-2 http://www.businessinsider.com/vehicle-miles-driven-2013-2 http://www.businessinsider.com/vehicle-miles-driven-2013-2 http://www.businessinsider.com/vehicle-miles-driven-2013-2 they are driving less miles per year http://www.businessinsider.com/vehicle-miles-driven-2013-2 they are driving less miles per year http://www.businessinsider.com/vehicle-miles-driven-2013-2 http://www.businessinsider.com/vehicle-miles-driven-2013-2 http://www.businessinsider.com/vehicle-miles-driven-2013-2 http://www.businessinsider.com/vehicle-miles-driven-2013-2