The NGB in '16 tried the concept at Fenway Park, where the event drew good crowds and turned a narrow profit despite unusual complexity and costs.
Coco Gauff's latest Grand Slam run helped put U.S. Open on pace to surpass attendance mark set last year.
The throwback theme is now a "permanent part of Darlington’s race weekend, and the official designation from NASCAR means no other track can copy it."
An average of 3,400 fans attended each session, but that may have been hurt by it taking place same weekend as the Travers Stakes.
The Packers decided not to play more than 30 players, including Aaron Rodgers and most projected starters, out of safety concerns.