The US auto industry has run into a rough patch, with the industry seeing a drop in sales for July, after the first cut in incentives since 2013.

All major US carmakers tempered their earnings guidance, according to Bloomberg, with Ford unveiling a five-year restructuring plan. The declining sales come amid speculation among investors that auto sales have peaked, and that demand will continue to weaken.

Higher interest rates have contributed to the pullback in discounts.

Shares of Ford and General Motors both dropped by as much as more than 2%, while Fiat Chrysler slipped by as much as 3%.