SCHAUMBURG, Ill. -

The pool of vehicles in the U.S. is getting larger.

As of June 30, there were more than 249 million cars on American roads — and the average age of these vehicles inched up from where it was a year ago.

That’s according to the latest Experian Automotive Quarterly Briefing released this week, which dissected vehicles in operation data along with a whole host of used-car market metrics.

The report indicates there were 249.4 million vehicles in operation during the second quarter (as of June 30), compared to 247.9 million a year earlier.

Just over a quarter of the cars on the road (25.2 percent) are from model-year 2010 or later, and 93.3 million vehicles are in what Experian called the “sweet spot” — model-years 2003 through 2009.

The average age of cars on the road in Q2 was 11.0 years, up from 10.9 in Q2 of 2013. However, the 15-year rolling age dipped from 7.7 years to 7.6.

The report also dives into year-to-date vehicle registrations. In the first half of 2014, there were 20.36 million used-vehicle registrations, down from 20.71 million in the same period of 2013.

New-vehicle registrations, however, climbed from 7.96 million to 8.29 million.