+1
The score history contains 200 rounds - older scores fall into oblivion.
On PC, it's no big pain to select & copy the scores from there and paste them into a spreadsheet. Did that long enough, but, TBH, it's worth the hassle only for number nerds.
Most of your "Legend noob" scores won't make it to the final 500, and it's more and more difficult to seed the good which count from the bad = "ranked but not counting to average".
As a Legend (and TM), it may be better to just save a note of your total ranked rounds # from your profile stats when you tier up - it will give you a hint to when you might expect saturation (500 L rounds).
Otherways, tracking don't ease the grinding!
Best recipe: Have fun!!