Basically Nemesis and CBeebies brings the crowds. I'm surprised that 2010 was so big, I guess the hype worked for Thirteen then!
Would be good to see those figures with the ride openings alongside for a comparison
Again there is no real significant increase of attendance in any year, baring the opening of Air 2002and Th13teen 2010.
I think Th13teen was well marketed, bringing in a lot of intrigue, and probably a lot of people wanting to ride to find what is going on.
I think that is one thing with gimmicky/ world first coasters, once you have ridden it once you are often not compelled enough to come back and ride it again, despite it being a good ride.