CARY, N.C. -

Through July, auction volume of late-model vehicles is up 4.2 percent from where it was after seven months of 2017.

That’s according to the latest Guidelines report from J.D. Power Valuation Services, which defines late-model, in this case, to be vehicles up to 5 years in age.

And the increase in that slice of auction volume gets a little bigger each month, and will likely culminate with a full-year increase well over 6 percent, according to J.D. Power.

The latest figures follow a July where there was a 5.1-percent month-over-month dip in late-model volume, but a 13.1-percent year-over-year hike, according to the report.

Driven by lease returns — of which there will likely be 14.2 percent more this year — the crop of vehicles aged 5 years or less is expected to climb 6.5 percent for full-year 2018, says J.D. Power.

That increase is down, but not dramatically, from the 6.6-percent uptick last year.

Late-model rental volume is expected to climb 8 percent, and what J.D. Power dubbed “regular retail purchase supply” is likely to jump 2.7 percent.

Look for next year to be the “peak” in supply, the company said.

In a separate report from RVI Analytics, analysts spotted a 15.9-percent month-over-month and a 4.6-percent year-over-year hike in overall auction transaction volume for July. That comes with a caveat, however.

“Although auction volumes are ahead of last year, more institutional consigners, especially rental companies and captive finance companies, are using alternative channels to realize a higher net result,” analysts said in the wholesale market report released last week.

“Alternative channels, including direct sales to dealers or customers can convert the asset into cash faster while eliminate auction fees and transportation expense,” the report continued. “It can also have the effect of boosting auction prices by reducing the supply in that channel.”

RVI is calling for continued increases in used-car supply over the next few years.

The RVI Used Vehicle Stock Index is likely to climb 6.8 percent this year, followed by 3.8 percent and 3.4 percent gains in the following two years, before scaling back 1.3 percent in 2021.

This is playing a role in the company’s predictions for declines in its Used Vehicle Price index. Though projected to climb 0.4 percent for 2018, the RVI UVPI – Real is projected to fall 2.9 percent in 2019 and dip 1.3 percent in 2020.

“The UVPI forecast is trending downward over the next two years.  This is due to strong new vehicle sales and high lease penetration leading to higher used vehicle supply over this timeframe,” the report notes. “In addition, continued high incentive spending leads to lower prices in the used vehicle market.”

RVI points out in the report that all of the data is through RVI, while the industry commentary and analysis is through Maryann Keller & Advisors, which is a member of the Automotive Intelligence Council.