This would be the first annual decline in auto sales since 2009, but it would still be the fourth best year on record after 2016, 2015, and 2000.
This isn't a huge concern - most likely vehicle sales will move sideways at near record levels. But the economic boost from increasing auto sales is probably over.
Click on graph for larger image.
This graph shows annual light vehicle sales since 1976. Source: BEA.
Sales for 2017 are estimate at the pace of the first three months.