How does Patch 3.7 affect Caitlyn's DPS?
Base Attack Speed reduced to 0.625 from 0.668
Attack Speed per level increased to 4% from 3%
Contrary to popular opinion right now, Patch 3.7's Caitlyn change isn't a total death sentence. It's still a pretty decent hit, but there was still a buff along with the nerf. The catch is that the nerf is a little more complicated than the patch notes imply.
Every champion in the game has a .625 base attack speed, which is affected by "attack delay"; what really happened to the "Base Attack Speed" parameter is that Caitlyn's attack delay was increased from .935 to 1.00. Riot has designed the game so that given the same items, attack delay makes some champions more suited to being physical damage carries than others. For example, champions like Morgana and Annie (1.08 delay) will have a lower marginal damage gain from items than Nidalee (.93) or Ezreal (.94).
In practice, the change means that each standard autoattack will have an additional delay before the missile is released, from .625/.935 = .668 to .625/1 = .625. This change trickles down to any attack speed increases, as any increased attack percentage will be increased by the same factor as the attack delay.
Keep reading to find out how the AS buff + delay nerf affect Caitlyn's damage per second!