Looking at one year is interesting, looking at several years is really interesting. Looking at the Theme Park attendance data I've been able to gather we get the following chart.
Unfortunately, I'm missing data for all of the parks. I'm missing individual park data for Disney from the 80's, the early years of USO in the early 90, and most of the data from Sea World.
From 1996-2002, MK, EPCOT, DHS, and USO saw declining attendance. DAK saw an initial spike in attendance in 1998 but the joined the downward trend. IOA saw a similar initial spike but was able to keep most of it's attendance during the period.
From 2003 - 2009 Something interesting happened, Disney started turning their attendance figures around while Universal continued to decline and IOA started declining and fast. So, the question becomes what happened during this time frame to cause the Disney's boat to start lifting while Universal's boat still sank. I've narrowed it down in my mind to 3 things.
First, aggressive discounting Discounting. The time frame saw the creation of Free Dining. In 2003 they offered book 4 nights get 3 nights free including tickets.
Second, Add to that, the creation of MYW ticketing in 2005. In 2004, extending a WDW ticket from 5 days to 7 days cost almost an extra $100. In 2005, under MYW going from 5 to 7 days cost $6. It was the original "lock it in". In 2004, $100 would almost get you 2 days at Universal. So your choice for that $100 was 2 days at Disney + water parks (going from 5-7 days required adding water parks at that time) or 2 days Universal.
Third First,
Disneyland's 50th anniversary. In honor of Disneyland 50th, WDW got 3 attraction in short order. Soarin' at EPCOT, and Lights Motors Action at DHS in 2005 and Expidition Everest in DAK in 2006.
At Universal, there wasn't much happening.
Ticket prices adjusted to try and compete with Disney. They started offering 7 day tickets for $85-$99. At IOA the only attraction they opened was the Sky High Seuss trolly train ride in 2006 that was supposed to be an opening day attraction. USF opened the Mummy, Shrek 4D, and Jimmy Neutron but all 3 were replacements for existing rides.
From 2010-12. Except for MK this year, WDW has been coasting along. The gains from the earlier period have held and growth has been 1-3% per year. At Universal the big thing that happened was Harry Potter. In 2009 WWOHP opened at IOA and in 2 years time it went from a dying park to one with record attendance. USF has stopped declining in attendance and is growing similar to WDW.
Putting 2013 in context to what came before. At Disney, MK saw significant growth primarily I assume to a full year stage 1 of New Fantasy Land. Epcot, DHS and DAK are still growing at about 2%. At Universal, USF saw significant gains in attendance with the addition of Transformers, Dispicable Me, and improved theming around the Simpson's ride. And this is despite the fact that WWOHP Diagon Alley is slated to open this year. IOA growth was inline with EPCOT, DHS, and DAK. The massive gains from 2010-2012 are holding.
Not to leave Seaworld out of the picture. They've been fairly steady. Up some one year, down some the next but the general trend was up from 1999-2009. 2010 saw a significant decline in attendance, probably attributable to WWOHP opening. Since then it's been fairly steady at that lower level.
The big question is what's going to happen in 2014-16?
