New vehicles' average transaction price fell below the manufacturer's suggested retail price (MSRP) for the first time in 20 months, according to data published by automotive research company Kelley Blue Book.

Vehicle prices turned hot after a pandemic-driven supply chain snag and an increased demand for private cars.

The average transaction price of a new vehicle in the U.S. declined 1.1% in March to $48,008 from February's $48,558. However, March prices rose 3.8% compared to a year earlier.

Top global automakers, except Toyota Motor Corp, reported a rise in first-quarter U.S. sales on improving shipments to dealers as vehicle inventories improve.

"Right now, in-market consumers are finding more inventory, more choice and dealers more willing to deal, at least with some brands," said Rebecca Rydzewski, auto-industry researcher at Kelley Blue Book's parent firm Cox Automotive.

In March, the average price for a new non-luxury vehicle, which includes brands such as Chevrolet, Ford, Hyundai and Nissan, was $44,182, a decline of $505 compared with February, but buyers continued to pay above MSRP for luxury vehicles, according to the report.