Add % HP damage dealt to the end game stats

Isn't it just a little annoying when someone goes even but flames about how they did so much damage at the end of the game, when they're playing Vayne, Kai'sa, etc. and were mainly attacking enemy tanks? Of course their damage numbers are going to be higher, because that stat doesn't account for the fact their damage is scaling with the enemy's HP.

So why not include the max health percent damage dealt on the graph? And I don't mean their percent of the overall damage, that's just another way of stating the flat numbers. As far as I can think at the moment, that'd have to mean separate stats to show what percent of damage they dealt to each enemy individually, since taking the whole enemy team's health still wouldn't work.