It seems like it is based on 30 games, and the 1st 3 are marked as quits so you start at 90%:
x x x F F ... F where x is quit and F is finished. So 27/30 = 90%.
I played 3 games and finished and was at 100%. (30 - F's).
Now, I played and had problems with lock-ups and people quitting and games hanging and was down to 80%. I have played 3 or 4 games and am still at 80%. Wha?
Well, I figured out why: Say that 80% in my case was: 24 F's followed by a mess of 6 x's because of problems. Then I play 6 games and DON'T quit. Now I have have 18F's, followed by 6 x's followed by 6 F's, still 80%. So THAT is why you can play and play and still now get rid of the x's. They have to flow through your games played until play 30 games after a quit.
Now, I think the reason they did this was if they started everyone at 1/1 (100%) and then on the 2nd game you had a lock-up you would be at 1/2 (50%). So they gave everyone 30games and the new games go in the end and the old roll out the back. That is why it went from 90 to 100% so quickly (the first 3 games were counted as quits) and they dissappeared. But after that it takes 30 games for a quit to roll through. When a F drops off the front and a F (finish) is added your % doesn't change.
So, I've repeated myself and I just would say don't take anyone's stats too seriously. They may come up with a way to not penalize those who stay with the game when others quit. I think I will quit playing multi player for a while until they get it figured out.
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