CM is right about the 88% thing. I've seen this often myself (and I've seen 77% and 66% too). This means you hit 8 of 9 fairways. Whether there are 1 or 2 par 3's, you can't EVER have 9 in the denominator.....pretty basic math.
At the same time, if the game is using 9 as the denominator, then you should never be able to hit 100% fairways, and we know that's not the case.
I think it is a glitch on some 9's, where the game doesn't do the math correctly.
I'm going to keep track of which 9's this happens on.