Yeah, as dominikk1985 says above, you have to include the costs of the event.
- Hiring the dome for 2 weeks (they have to set up the court etc) would cost in the millions.
- Lighting - hundreds of thousands for an event like that
- Getting the tennis courts installed (including the practice court), wouldn't be surprised if costs crept up near a million.
- signage, posters, media placement - millions of dollars
- design work - tens of thousands or more per year
- staff - in the millions of dollar once you consider all the staff needed for an event like this (a GM, doctors, security, chefs, hosts, selectors/trainers for the ballkids)
- tv gear - specialist sport coverage also including the tech for all the commentator's booths to be hooked up/wired in.
- Hawkeye hiring
- Media centre space
- Accounting/legal consultancy
Costs for events like these are plenty and add up very quickly. I doubt we'll see the operating budget for it anytime soon.
FWIW, the revenue calculations in the original post seem high also.
Original Pro Staff 85, leaded to 370g, hybrid poly/syn gut set-up, 48-52-ish lbs.