FORT LAUDERDALE, Fla. –

AutoNation enjoyed a 3-percent year-over-year hike in its retail new-vehicle sales during September, and leading the increase for the dealer group were domestic sales, which improved double digits.

Overall, AutoNation sold 18,670 new cars last month, up 3 percent from September 2010. The retailer has seen a year-to-date increase of 6 percent through the first nine months of the year.

During September, the domestic operating segment at AutoNation had sales of 6,257 new vehicles, a 17-percent gain. Meanwhile, new import sales fell 8 percent year-over-year at 8,778 units.

The premium luxury segment showed a 16-percent hike with 3,635 sales.

For the third quarter, AutoNation incurred a 1-percent year-over-year drop in new-car sales due to the Japanese car supply issues stemming from the earthquake earlier this year, officials said.