Used prices remain elevated — the second quarter holds the record for highest used prices in history, and Q3 was the highest third quarter on record — and analysts are narrowing it down to two factors the industry expects are behind this trend.

According to the Q3 2014 Used Vehicle Market Report from Edmunds.com, it comes down to one, the fact that used vehicles being sold are younger; and two, low gas prices making large vehicles more attractive.

But first, let’s get down to the bottom of it — and that may have to do with age.

One of the main reasons behind the recent spike in price, Edmunds.com asserts, is used vehicles in the lanes and on the lots are simply younger.

Due mostly to an increase in lease returns — units which are often only 1 to 3 years old — Q3 had seen a higher level of newer used vehicles.

According to the report, one out of five used vehicles sold in 2014 were between 1 and 2 years old.

In comparison, this rate had dropped down to 14 percent in Q3 2013.

“This higher mix of newer used vehicles has led to an upward pull of used car prices,” Edmunds.com analysts said.

The second factor pushing high used prices, is low gas prices, which are pushing more consumers to buy larger vehicles — which, of course, are often more expensive.

“The U.S. is experiencing record low gas prices with 2014 marking the fourth year in a row that fuel costs have stayed within $3 per gallon,” the report stated.

Edmunds analysts contend this trend has causes many of the light truck segments to experience sizable gains in used values as car shoppers are willing to purchase them again.

“These are generally larger vehicles which command a higher price tag,” analysts pointed out.

The Edmunds report offered this example: the midsize traditional SUV category saw prices lift by a significant 18.7 percent year-over-year in Q3.

“These vehicles saw so much contraction during the recession that many analysts predicted their exit from the market, however, stable fuel costs and increasing niche market demand has these vehicle’s transacting nearly 19 percent higher than 2013 Q3,” Edmunds.com analysts explained.

For comparison, take a look at one of the smaller, more fuel-efficient segment’s price movement. The compact car segment, for example, only saw a 2.1-percent year-over-year price spike in Q3.