How much more prices will rise in the process remains to be seen. But according to TrueCar, the price of the average new vehicle jumped 1.9 percent compared to last year, to $31,831. Used vehicle prices, meanwhile, have increased 5.1 percent, to an average $16,335.
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The sharp price gains in previously owned vehicles have been due, in part, to a shortage of "nearly new" off-lease vehicles coming out of the industry's worst downturn in decades. TrueCar said it expects this supply to be more normal in 2015, with 10 percent more vehicles that are five years old or younger being available.
"This is the last year we expect used supply to be impacted by the recession's pullback in new vehicle buying," said Larry Dominique, head of ALG, the analytics division of TrueCar.
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That could mean a price break for used vehicle buyers. Hearst's Black Book, which tracks auction and dealer traffic, has noted that prices have already begun to fall in some previously owned segments of the market.