Guys the TOP20 is right because it is per developer... they just list the best seller game for that developer.
Sumo digital did a lot of games for different platforms.
The Polyground Games % for Xbone have Forza 5 and Forza Horizons 2.
Its Turn 10's game....and who are polyground, its playground.
And Sumo did forza Horizon for xbox 360 and had no involvement with Xbox ONE - it mentions xbox one next to the game but has no % for xbox one!?
this chart seems to be a bit of a mess to me.