Used-vehicle sales ended last year with a bang compared to a year earlier, though they were flat from November.

Cox Automotive data show a 12% year-over-year bump to 1.4 million units, while the lack of month-over-month movement increased days’ supply by one day to 48.

“December usually sees a drop in used-vehicle retail sales, but this year they showed a stronger seasonal trend and were significantly higher than last year,” said Cox Senior Analyst of Economic and Industry Insights Scott Vanner in a press release. 

“December marked the second month of double-digit year-over-year sales growth, capping off a positive year for used-vehicle sales.”

Certified preowned models, meanwhile, increased 4% over November to nearly 217,000 units but were down year-over-year by 5%, said Cox, which pointed to one fewer selling day and the scarcity of off-lease units and trade-ins.

Cox predicts that used sales will increase a modest 1% this year to 20 million units due to still-constrained inventory lingering from low pandemic-era production, along with limited off-lease units.

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