Britney's tour was her comeback tour, the one after that did 70m.
And the ones previous to that did way less.
Actually if I'm not wrong her FF tour is her second highest grossing?
And I said normally in my post indicating that there are exceptions
Something that I've always thought was interesting was how the ethnic background of some artists make them more popular in certain regions.
So Selena Gomez, Demi, Jennifer Lopez, Christina are Latinas so they are very popular in Latin America.
Beyoncé and Rihanna are very popular in Africa and the Caribbean.