Car sales continue to soften from the highs of last year.

And May sales unchanged from April would mean no contribution to growth this month:

U.S. Light Vehicle Sales increase to 17.4 million annual rate in May

by Bill McBride

Based on a preliminary estimate from WardsAuto, light vehicle sales were at a 17.37 million SAAR in May (Preliminary estimate excluding Jaguar Land Rover and Volvo).

That is down about 1.5% from May 2015, and up slightly from the 17.32 million annual sales rate last month.