There might be a seasonal factor to the August bump, as this survey isn't seasonally adjusted.

“August brought a stop to wholesale price declines, though it was only a small reversal of the larger magnitude declines so far this spring and early summer,” said Chris Frey, senior manager of Economic and Industry Insights for Cox Automotive. “Historically speaking, the monthly figure aligns with the 0.3% average we’ve seen since 1997... Used market conditions have been quite consistent for a few months and are not likely to change much, even with the larger push toward balance; sales are slightly stronger than expected, inventory remains tight, and prices are holding at levels around 6% below last year at the same time. These factors are expected to prevent any substantial decline in wholesale prices through year-end.”

In any case, those who were looking for a fast return to the pre-covid trend will have to keep waiting.