Auto retailer AutoNation reported healthy fourth-quarter revenue gains as sales benefitted from improved inventories.

Gross profit, though, was down 5% to $1.2 billion, the company said.

The Florida-based auto retailer, one of the country's biggest, reported a 1% year-over-year revenue increase to $6.8 billion as its new-vehicle and after-sales growth balanced fallen used-vehicle sales.

New-vehicle revenue rose 7% to $3.4 billion and after-sales revenue by 11% to $1.1 billion while used-vehicle revenue fell 12% to $1.9 billion.

"Our results demonstrate the strength of our business model. We enjoyed excellent new vehicle unit sales and competed well in a dynamic used vehicle market,” said CEO Mike Manley.

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