McLEAN, Va. -

Wholesale prices of used vehicles up to eight years old fell by 2.6 percent in August, and for the first time in several months, depreciation in luxury segments outpaced that of mainstream ones, according to NADA Used Car Guide’s latest Guidelines report.

August’s results, while in line with expectations for the month, represented the largest monthly decline thus far in 2016.

As a result of August performance, NADA Used Car Guide’s seasonally adjusted used vehicle price index fell by 0.4 percent to 118.6.

Luxury compact car and luxury midsize utility prices fell the most for the month at 3.5 percent each — notably worse than the pair’s previous three-year combined 2 percent decline. Luxury midsize and large car prices fell by 3.4 percent and 3.2 percent, respectively.

Luxury compact utility and luxury large utility prices performed better than the overall industry average at 2.3 percent and 1.8 percent, respectively, which was in line with their previous three-year combined 2.1 percent decline.

Large utilities led losses among mainstream segments at 3 percent. This segment’s August performance was the worst since October 2014 and ended a 19-month run on declines that averaged 0.6 percent. NADA Used Car Guide attributed the segment’s steep losses to an influx of late-model 2015 units to the wholesale marketplace. Volume picked up by almost 59 percent, while prices for vehicles such as the 2015 GMC Yukon fell by up to 4.7 percent.

Losses for subcompact, midsize and large cars were higher than the industry average (at a combined average 2.8 percent) but were typical for August. What’s notable is that after three straight months of nearly 3 percent price declines, compact car prices saw prices fall by only 1.9 percent in August — the least of any car segment for the month.

Also in August, midsize utility and midsize pickup prices fell by 2.4 percent each, while compact utility prices fell by 2.1 percent. Large pickup prices fell 1.2 percent; year to date, monthly declines in this segment have averaged 0.1 percent. Midsize van prices fell by 1.1 percent, which was better than the segment’s previous three-year 1.8 percent decline for the period. Prices for this segment are typically softest in September and October as rental fleet units flood the market.

Year-over-year trends

Through August, NADA Used Car Guide’s used vehicle price index was 3.6 percent below last year’s eight-month average. Used vehicle prices were 13.2 percent lower through August relative to all of 2015. Last year, depreciation reached 10.3 percent over the same period.

Subcompact car prices fell the most over the eight-month period, dropping by an average of 21.1 percent vs. the same period a year ago.

The only segment that saw improvement relative to last year was large utility: Prices for the segment fell by 7.1 percent through August 2015 compared to 6.3 percent in 2016.

September and full-year forecast

NADA Used Car Guide’s September 2016 forecast has prices of vehicles up to 8 years old falling by 3.3 percent to 3.8 percent compared to August. This is in line with the 3.4 percent decline averaged for last September.

Subcompact car prices are expected to drop by about 4 percent, while compact, midsize and large car prices should fall by an average of 3.8 percent — similar to last September.

Compact utility and midsize utility depreciation is expected to reach 3.4 percent, while midsize van prices are expected to fall by about 3.9 percent. Large pickup and large utility depreciation should increase with prices declining about 3 percent. Luxury segment losses are expected to average between 2.9 percent and 3.5 percent.

Excluding December, monthly losses are expected to be slightly softer for the remainder of the year. As a result, NADA Used Car Guide’s full-year forecast has prices down by an average of 4 percent on an index basis from 2015.