The year-over-year seasonally adjusted decline for June also was large — an additional 2.7 percent drop from May’s annualized 7.6 percent decline, Frey said in a news release.

“As mentioned last month, auction prices were lower in the fall last year and we expect these increasing year-over-year moves to shrink in the months ahead as the market normalizes,” Frey said.

Buyers at wholesale auctions appear to have taken an “early summer break,” Frey added.

He noted Cox is expecting less volatility in wholesale price movements through the end of the year.

Wholesale price declines in the second quarter effectively erased price gains the industry saw in the first quarter, Cox Automotive Chief Economist Jonathan Smoke said Monday during a quarterly call about the Manheim index.

“The declines in May and June have created some worries about the declines continuing … but let me go ahead and spoil the ending and tell you that we do not expect the remaining months of the year to deliver declines like we saw in the spring,” Smoke said.

Average nonadjusted wholesale prices for 3-year-old vehicles, the largest model year cohort at Manheim’s auctions, declined an aggregate 3.8 percent over the last four weeks, Cox reported.

Cox Automotive estimated the retail used-vehicle supply in the U.S. was at 45 days at the end of June, down from 49 days at the end of May and down from 52 days at the end of June 2022. Wholesale used-vehicle supply is estimated to have ended June at 24 days, unchanged from the end of May and down from 26 days at the end of June 2022.

Black Book index

A second industry indicator of wholesale used-vehicle prices also recorded another decline in June.

Black Book’s Used Vehicle Retention Index — calculated using Black Book’s published Wholesale Average value on 2- to 6-year-old used vehicles and weighted based on registration volume and adjusted for seasonality, vehicle age, mileage and condition — fell by 1 percent in June from May.

The Black Book index fell 1.8 points to 173.6 in June. That figure is 9.3 percent below where it was at the same time in 2022. And it’s about 51 percent higher than in March 2020 when the pandemic began.