system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5. How can car dealerships be selling 2016 models already when it's only May of 2015?
gpt
The "model year" of a car is mostly a marketing thing, and not an actual description of when the car was made.  A "20XX model" car is generally used to mean "the model that will be on sale for the majority of the year 20XX."  In the US, there is only one regulation surrounding which year number they can use:

>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. For example, this means that a 2017 model year vehicle can legally go on sale on January 2, 2016.

So you can't sell a "2017 model" car in 2015.