In the United States, automobile model year sales traditionally begin with the fourth quarter of the preceding year. So model year refers to the "sales" model year; for example, vehicles sold during the period from October 1 to the next December 30 is considered one model year.[1] In addition, the launch of the new model year has long been coordinated to the launch of the traditional new television season (as defined by A.C. Nielsen) in late September, because of the heavy dependence between television to offer products from automakers to advertise, and the car companies to launch their new models at a high-profile time of year.[2]
In other cases, products of a previous model year can continue production, especially if a newer model hasn't yet been released. In that case, the model year remains the same until a new model is introduced. This is to ensure that the model will be seen by the public, and will actually sell an amount of vehicles before a new vehicle model is produced, and people will look at the newer model rather than the previous one.
In the United States, for regulation purposes, government authorities allow cars of a given model year to be sold starting on January 2 of the previous calendar year.[3] This has resulted in a few cars in the next model year being introduced in advertisements during the NFL's Super Bowl.
