The average value of used fleet vehicles increased 1.5% to $13,758 in June from May, but remain 4.3% higher than a year ago, according to KAR Auction Services' ADESA unit.

For the first time this year, wholesale used fleet units failed to outpace vehicles consigned for sale by manufacturers and dealers. In June, manufacturer vehicles were up 4.6% from May and are up 6.8% from a year ago, while vehicles from dealers were up 1.6% from a month ago and up 7.3% from a year ago.

The overall market in June saw wholesale used prices fall 1.6% to $11,478, which was 5.4% ahead of a year ago's average. Car and SUV prices were hardest hit, while van and pickup truck prices held up better, wrote Tom Kontos, KAR's chief economist, in his monthly commentary.

"The 2019 spring tax season used vehicle market came to an end appropriately in June, as average wholesale prices fell on a month-over-month basis, although they were up year-over-year," Kontos said. "Solid retail used vehicle sales again provided demand-side support for wholesale values."

Categories with a significant number of former fleet vehicles, such as midsize sedans and midsize SUVs, fared well. Midsize car values increased 5.7% to $12,600, while midsize SUV values increased 2.6% to $21,094. The fleet lease units tracked were three years old with between 36,000 and 45,000 miles.