The average transaction price for a new light vehicle in the U.S. was $37,590 in September, a 0.6% year-over-year increase, according to Kelley Blue Book.

Midsize pickup trucks are seeing the biggest increase to average transaction price while electric vehicles experienced the biggest year-over-year decline in September.

In terms of manufacturers, Hyundai-Kia saw the biggest overall rise in average transaction price while American Honda saw the biggest decline.

"Transaction prices are still strong, but the growth has almost stalled, as retail demand is weakening," said Tim Fleming, analyst for Kelley Blue Book. "Despite automakers pulling back their production this year, it may not be fast enough. Incentives are rising, averaging about 10.5% of average transaction prices and nearing levels from 2017 when industry sales saw their first decline since the recession.

While incentives may be helping sales on the new-vehicle front, they will have a negative impact on the vehicles’ residual values, which will affect resale values when the vehicles enter the used market.