Editor's note: An earlier version of this story described incorrectly the change in California's retail vehicle sales in 2015.

For the first time in seven years, U.S. dealership new-vehicle throughput -- the average number of units sold per store -- is expected to decline, according to most light-vehicle sales forecasts and data from Urban Science, a retail consulting firm.

Urban Science, of Detroit, reported the average dealership throughput last year was 966. The company forecasts throughput will be 960 this year. That’s still higher than 2014’s 921.

Throughput is defined as the number of sales divided by the dealership count. Most forecasts for U.S. new light-vehicle sales range between 17.3 million and 17.7 million vehicles, compared with last year’s 17.5 million. U.S. dealership count has remained relatively flat since the end of 2015, making the possibility of a new throughput record “questionable,” said Mitchell Phillips, global data director at Urban Science.

Urban Science released the forecast as part of its 2016 midyear Automotive Franchise Activity Report this week.