number of cars on the road in us
Passenger vehicles in the United States According to the Bureau of Transportation Statistics for 2012, there were 254,639,386 registered vehicles. Of these, 183,171,882 were classified as "Light duty vehicle, short wheel base", while another 50,588,676 were listed as "Light duty vehicle, long wheel base". Another 8,190,286 were classified as vehicles with two axles and six or more tires and 2,469,094 were classified as "Truck, combination". There were 8,454,939 motorcycles also listed along with 764,509 buses.[4]
Lane The widths of vehicle lanes typically vary from 9 to 15 feet (2.7 to 4.6Â m). Lane widths are commonly narrower on low volume roads and wider on higher volume roads. The lane width depends on the assumed maximum vehicle width with an additional space to allow for lateral motion of the vehicle.