STAMFORD, Conn. -

Wholesale values remained on the rise during June, climbing modestly from May, while also besting year-ago levels by almost 17 percent, according to RVI Group.

But with gas prices slowing down, so did the values of smaller vehicles, the company said in the latest RVI Market Update.

Overall, wholesale prices climbed 0.4 percent from May and showed a 16.7-percent year-over-year gain. Specifically, the RVI Used Car Price Index was 1.408 during June, compared to 1.403 last month and 1.207 in June 2010.

Driving these gains was the low level of used supply, RVI’s Rene Abdalah explained to Auto Remarketing on Wednesday.

"Supply continues to be at very low levels and that’s going to continue," he said, adding that this bodes well for used prices remaining stable.

Breaking it down by segment, many of the smaller classes led the list of month-over-month declines, RVI indicated, noting: “Smaller vehicles took a step backwards as gas prices eased in June.”

Abdalah said gas prices have declined about $0.10 to $0.20 per gallon since May.

The heaviest price decrease from May was seen in the sports car segment, where prices fell 3.2 percent, followed by small pickups (down 2.4 percent).

Likewise, subcompacts were off 1.5 percent and small sedans fell 1.1 percent.

Conversely, the heftiest sequential gains were spotted in the luxury full-size sedan segment, which was up 3.8 percent. Additionally, full-size SUVs climbed 2.6 percent and full-size pickups jumped 2.4 percent, as they commanded the second- and third-highest increases from May, respectively.

"That’s a complete gas-price flip," Abdalah noted. In other words, lower gas prices pushed down smaller segments, but helped to boost the values of larger segments.

That said, officials stressed that "full-size SUVs and full-size pickups remain the two worst segments in annual increases." Full-size SUVs were up only 3.2 percent year-over-year and full-size pickups were up just 3.7 percent. All other segments climbed double-digit percentages.

The reason why full-size SUVs and full-size pickups trail their peers, again, boils down to gas prices.

"Althought they’ve improved in the past couple of months, they’re still relatively high," Abdalah said of fuel costs, nothing that the larger segments "have not seen the recovery that we’ve seen in the rest of the market." 

The greatest year-over-year increase was in the subcompact segment (up 43.5 percent). Next on the list was the compact segment (up 30.1 percent), followed by small sedans (up 25.7 percent).