Subaru and Audi dealerships improved last year in the key metric of throughput. Hyundai and Lexus backtracked.

Dealership throughput is an indicator of a brand's health. When more vehicles have been sold through the same number of rooftops, those dealerships' profitability has probably risen.

Subaru has been raising its throughput steadily by increasing its U.S. sales while holding its dealership count unchanged.

The brand, which sat at No. 10 in the rankings as recently as 2013, has climbed its way up to No. 5.

Subaru's U.S. sales rose 5.3 percent last year to a record 647,956 vehicles, leading its average throughput to climb to 1,028 sales per franchise, up 4.9 percent, according to an analysis of Automotive News' annual exclusive dealership census, compiled by the Automotive News Data Center.

Subaru thus became the fifth marque to top the 1,000 units per store level, joining Toyota, at 1,720 in 2017; Honda, 1,420; Nissan, 1,329; and Lexus, 1,282.

Subaru, which is forecasting another year of record U.S. sales in 2018, remains committed to its dealership count and has no plans to add dealers to its network, a spokesperson wrote in an email to Automotive News.

Meanwhile, Audi is also swimming its way up the brand-by-brand rankings. It came in at No. 10 this year, up from No. 11 last year and No. 15 in 2013.

Throughput leaders Top 10 brands in sales per franchise Brand 2017 unit sales per franchise 2016 % change Rank Toyota/Scion 1,720 0.50% 1 Honda 1,420 0.60% 2 Nissan 1,329 0.50% 4 Lexus 1,282 -8.30% 3 Subaru 1,028 4.90% 6 Mercedes-Benz 979 -1.70% 5 BMW 892 -3.30% 7 Ford 807 0.40% 10 Hyundai 794 -13.50% 8 Audi 763 5.20% 11 Source: Automotive News Data Center

Audi added 10 franchises last year, pushing the count to 302 franchises as of Jan. 1. But its sales grew 7.8 percent — in a U.S. light-vehicle market that was down 1.8 percent — to 226,511. Audi's throughput therefore increased 5.2 percent to 763.

In 2017, U.S. new-vehicle sales fell 1.8 percent to 17.2 million, while the tally of car and light-truck franchises eased 0.2 percent.

The result was a 2.2 percent industrywide slide in sales per franchise to an average 532 vehicles.

On Jan. 1, the number of light-vehicle dealerships in the U.S. stood at 18,327, up 0.4 percent, or 66 more than the same period last year.

Exclusive outlets accounted for 37 percent of all franchises, or 11,926 out of 32,271.

The brand-by-brand analysis shows that of the 42 brands in the census, throughput rose at 18, fell at 21 and held unchanged at one. Two other brands — Alfa Romeo and McClaren — were new to the list.

A franchise is an agreement that gives a dealer the right to sell a particular brand of new vehicles. A dealership is the building in which one or more of those vehicle brands is sold.