Lithia Motors Inc., the fourth-largest dealership group based in the U.S., appears poised to move up in Automotive News' rankings, which are based on retail sales of new vehicles.

The Medford, Ore., auto retailer is hard on the heels of third-ranked Group 1 Automotive Inc., of Houston. And several major dealership acquisitions by Lithia this year could lift it to No. 3 eventually, depending in part on Group 1's buy-sell activity.

Those rankings are based on the most recent list — covering 2016 sales — of the top 150 dealership groups based in the U.S., as tallied by the Automotive News Data Center. Group 1's 2016 global new-vehicle retail sales totaled 172,053, to Lithia's 145,772.

The data center is crunching the numbers as dealership groups respond to its latest sales survey. New rankings based on 2017 sales will appear in the March 26 issue of Automotive News.

Separately, Group 1 and Lithia have released sales figures along with their earnings for 2017.

According to their 2017 earnings statements, Lithia had retail sales of 167,146 new vehicles last year, all in the U.S. Group 1 had 172,200 globally, and 127,141 in the U.S. It also owns dealerships in the U.K. and Brazil.

Lithia's sales gains in 2017 were partly from acquisitions. It has continued to buy stores in 2018. It doesn't forecast unit sales for its acquired dealerships, but its projected additional revenue hints at unit sales gains ahead.

Already this year, Lithia has added more than $1.3 billion in annual revenue through buy-sells.

In January, it bought Ray Laks Honda and Ray Laks Acura in Buffalo, N.Y. On Feb. 27, it bought Day Automotive Group in suburban Pittsburgh, which sells Audi, Volkswagen, Chevrolet, Ford and Subaru vehicles, according to its website. Day Automotive is estimated to generate $340 million in annual revenue.

On March 1, Lithia bought six dealerships from Prestige Family of Fine Cars in Bergen County, N.J., in a deal expected to generate $900 million in additional annual revenue. The deal adds BMW, Mini, Mercedes, Toyota and two Lexus dealerships to Lithia's portfolio.

Prestige owns more stores that were not sold to Lithia, said buy-sell adviser Alan Haig, president of Haig Partners in Fort Lauderdale, Fla., who represented Prestige in the transaction.

Meanwhile, Group 1 in January added a Land Rover franchise in the U.K. and acquired Audi and Subaru franchises in El Paso, Texas, for combined additional annual revenue of about $100 million.

CEO Earl Hesterberg also told analysts the benefits from corporate tax-law changes puts Group 1 in a stronger position to make more acquisitions.