Motorists traveled 0.3% fewer miles on U.S. roads and highways in June compared with a year earlier.
The numbers come from the U.S. Department of Transportation said in a monthly report Wednesday.
Drivers logged an estimated 279.7 billion vehicle miles in the month.
Miles have risen 0.8% in all of 2019 compared with a year earlier.
Reuters reports the data can be used as an indicator of demand for gasoline and diesel.