U.S. retail used-vehicle sales jumped more than usual last month as consumers started taking advantage of tax-refunds season.

The 16% jump over January deliveries to about 1.6 million units is up 6% year-over-year, Cox Automotive said.

Used days’ supply was consequently down eight days to 42, three days off a year earlier.

The bump was “the largest jump seen in recent years,” said Cox Senior Analyst of Economic and Industry Insights Scott Vanner.

Certified preowned sales alone, though, were essentially flat from January and down 3% year-over-year at just under 204,000 units, Cox said.

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