The 100th Indianapolis 500 did such an extraordinary box office last year, drawing the first sellout in race history with an estimated crowd of 350,000, that race officials understood that it would be virtually impossible to match ticket sales for the 101st race on May 28.

Mark Miles, the chief executive for Hulman & Company, which owns Indianapolis Motor Speedway and the IndyCar Series, set a more modest benchmark: Get half of the 130,000 increase in attendance between the 2015 and 2016 races to return in 2017.

A crowd of about 275,000 would serve as another key metric for the famous race, and the open-wheel series in general. Nearly three months before the Indy 500, Miles said in an interview this week that attendance is expected to be in that vicinity.

As a result, Miles said of the series, “I don’t see any cap to our growth.”

He was speaking by telephone from St. Petersburg, Fla., where the IndyCar Series will open Sunday with a race on a temporary street course. The schedule has been expanded to 17 races from 16, with an Aug. 26 event added at Gateway Motorsports Park in Madison, Ill., outside St. Louis.