Last years World Champs and other meets suffered rather poor attendence figures.
50,000 over 4 days would mean a close to sell-out (regular capacity is about 12,500), but I don't think that those figures will be met after this weekend reading all the complaints about air-fares, hotel and rental car costs in Eugene.
Also, the regular (old) Hayward field crowd is getting older, so Tracktown USA and USATF in my opinion need to figure out how to attract sufficient people to the stadium to make it look rather full (also to make it look better on TV).
So what numbers of attendance would be considered good and where will it be regarded as a failure?