Or do they? I tried to look up their methodology ... I admit I didn't look very hard ... actually only about 5 seconds, but I found this being quoted on the webs:
Let me try to break that down ...
- statistics furnished directly by the operators
- historical numbers [i.e. old statistics furnished by the operators]
- financial reports [i.e. statistics furnished by the operators]
- the investment banking community [who give them statistics furnished by the operators]
- local tourist organizations [who give them statistics furnished by the operators]
It's not completely bogus. The reason for checking the same statistics from multiple sources is because if someone is telling fibs, they will seldom be able to keep their story consistent when they tell it several times to different people.
In other words, AECOM apparently counts nothing, but depends on the honesty of the theme park operators, with some cross-checking for consistency. They might be able to cross-check against hotel and airline bookings, but really ... how do they know how many days were spent at IOA and how many at the beach? And note that the cross-checked information is generally company-wide (financial reports and banking) or city-wide (tourist organizations). There are apparently no consistency checks available to confirm the supposed numbers of DHS versus AK versus USF.
In other words, there's no precision in anything but turnstile clicks, and TEA aren't privy to those.
From prior experience, I can tell you that a lot of supposed "analysis" of industry and finance is no such thing. When I was at a publicly traded company we were frequently puzzled at how "analysts" came up with consensus estimates of where a company's earnings would be for the impending quarter-end. Turns out, mostly they just phone the company and the company tells them what the expected earnings are. Plus or minus whatever spin or bump the company wants to achieve on the actual announcement day. Like, "Wow, XTRAtech came in exactly $0.01 ahead of consensus estimates again, for the 683rd quarter in a row! How do they do that?" Well ... guess.