The improving economy and growing consumer demand for newer, more fuel-efficient vehicles that include the latest safety features and in-car connectivity are driving the trend.
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"Right now the auto industry is in the midst of a cycle where sales and pricing are very strong," said J.D. Power's Deirdre Borrego. "I'm cautiously optimistic that will continue at least through next year."
But it's not just retail auto sales—vehicles that are sold directly to consumers—that are expected to see a boost. The firm's forecast comes as Wall Street analysts are predicting total U.S. industry sales—which also account for the sale of fleet vehicles to rental car companies, corporations and government agencies—could top 17 million next year.
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The increase, while welcome news for the auto industry, has led some to question whether the strong market is sustainable.
"As long as the economy remains strong and interest rates stay relatively low I think sales will hold up well," Borrego said.