Writing a paper on The meta changes in lol. Help needed.

Hi, I am currently writing a paper on the changes in the lol meta. This is what I need help finding.

1. Statistics. A LOT of Stats. The older the better.
2. Any meta changes that you guys know of. I have only been playing for about a year, so any meta changes for S1-3 would be wonderful
3. Any ideas you guys can think of. The more the better. If you guys want to see the paper I should be able to share it in about a week or two. Thank you in advance.