Clarity - Damage Dealt

At the end of the game, the stats display how much damage was dealt by a particular champion throughout whole game. But what if you wanted to compare two games, find out in which one you dealt more damage. But the first game's length was 21 minutes and the second one's was 56 minutes. There is no way to do it right. What if we were able to see how much damage we dealt from the start and until the exact time we set. Examples - damage dealt: 5 minutes passed - 4k, 10 minutes passed -11k, 15 minutes passed - 16k, etc..