Note: this article adopts the U.S. Department of Transportation's definition of a passenger vehicle, to mean a car or truck, used for passengers, excluding buses and trains. The United States is home to the second largest passenger vehicle market of any country in the world second now to China. Overall, there were an estimated 255.8 million registered passenger vehicles in the United States in 2013. This number, along with the average age of vehicles, has increased steadily since 1960, indicating a growing number of vehicles per capita.