Growth seems to be steady. Good new attractions, or bad new attractions (or no new attractions in a specific park in a given year) over the last many years and attendance at both USF and IOA has continued to increase. Looking at the yearly TEA report shows steady growth year over year for both parks with really only Diagon Alley giving a significant/massive boost:
2012:
USF - 6.195m visitors - Minion Mayhem was new that year
IAO - 7.89m visitors - Nothing new
2013:
USF - 7.062m visitors - Transformers ride was new that year
IOA - 8.141m visitors - Nothing new
2014:
USF - 8.263m visitors - Diagon Alley Opens
IOA - 8.141m visitors - Nothing new (unless you count Hogwarts express)
2015:
USF - 9.585m visitors - Nothing new
IOA - 8.792m visitors - Nothing new
2016:
USF - 9.998m visitors - Nothing new
IOA - 9.362 - Kong was new that year
2017:
USF - 10.198m visitors - Fallon new
IOA - 9.549m visitors - Nothing new (and Dragon Challenge closed in Sept).
2018 numbers aren't out yet, but USF got F&F (which everyone agrees sucks), and IOA had gone a full year without Dragon Challenge, but I can wager that both parks will have increased another 2-6% in attendance regardless. The only things that look to move the needle beyond the 2-6% range seems to be truly massive expansions like Diagon (and Hogsmeade before it).
So pulling back on some of the yearly bits that were previously planned and putting the emphasis on FW (while still opening Hagrids and JP Coaster between now and then) is probably an ok move for them financially, and probably means FW opens sooner (2023?) rather than later (2024-2025)
Really enjoyed this breakdown! Very informative.
On another note, I'm not sure why people are saying Universal will be in trouble by holding off on new attractions. I'm not sure what is the percentages of Floridians to non-Floridians that make up the guests to Universal, but someone visiting from a distant location is most likely going to take advantage of visiting Star Wars World with Harry Potter World.
Every time I talk to someone in New York or in Texas about Orlando theme parks, majority of the time people don't even realize its two different companies. The other day I heard someone say they wanted to visit Disney so that they could see the Harry Potter World.
The argument may be sound if UNiversal makes most of their money from Floridians, but as far as outsiders go they are attracted by the IP themed land. The Star Wars World is going to increase guests in Universal, because if they are spending money to see Star Wars, they are going to want to see the other big IP world in the city.
I actually think that holding the coaster off til 2021 is a great idea. If they are going to revamp River Adventure into Jurassic World (seems inevitable now unless the ride in hollywood tanks), then it would be great marketing to reveal a whole new themed land. A lot of people outside Florida don't even know that there is a Jurassic Park land. They have heard of Harry Potter and now Star Wars. Universal could open the new River Adventure, the coaster and whole surrounding area devoted to Raptors with a kick ass permanent raptor encounter. They could even revamp the Discovery Center, and the camp for not too much cost.
Imagine a whole other world being advertised with Harry Potter. Jurassic World may not be as big as Star Wars or Harry Potter, but it will turn more heads in my opinion than Avatar.
If in that time they can improve their parades, projection shows, and live entertainment options, then Universal would have solidified their parks for those not living in Florida or not theme park fans.