Supplies of unsold vehicles in the U.S. increased for the fourth consecutive month in April, rising above 4.1 million units for the first time since June.

Meanwhile, the industrywide days supply retreated slightly from a year ago thanks to a strong selling rate.

Automakers started May with an estimated 4,102,100 unsold vehicles on hand, a 73-day supply, according to the Automotive News Data Center. Both inventory measurements were down from the same point a year ago, when automakers and dealers were sitting on an estimated 4,157,200 vehicles, a 76-day supply.

The total number of units has grown at a steady clip through each of the first four months of this year. However, the mix of unsold vehicles closely matches what’s selling, with 31 percent of inventory in cars, and 69 percent in pickups, utility vehicles and vans.

Among automakers, Subaru of America had the tightest supply at the beginning of May at 44 days, followed closely by BMW of North America and Mercedes-Benz USA, both at 46 days. On the other end, Mitsubishi Motors N.A. had the largest supply, at 119 days, followed by Nissan North America and Jaguar Land Rover at 88 days.

At a brand level, Subaru’s 44-day supply is just tighter than Mini at 45 days, followed by BMW and Mercedes-Benz, both at 46. Only three brands had more than a 100-day supply: Jaguar at 113, Mitsubishi at 119 and the struggling Fiat brand at an industry-worst 133.