Las Vegas’ first Grand Prix in four decades was supposed to be the latest big sports win for Sin City. But in the days and weeks leading up to Thursday’s start of racing, ticket prices and hotel room rates have been tumbling, a sign of dwindling excitement around the event.

Liberty Media, the owner of F1, has started to lower profit expectations for the race, blaming unexpected costs.

The falling prices raise questions about whether the race’s backers overestimated the sport’s popularity in the U.S., expanded too quickly or just charged too much at a time when overall viewership for F1 on TV is sliding.