First of all this satement is wrong:
HTML Code:
$statscache['topposterpercent'] = round(100 * ($topposter[posts] / ($totalposts)), 2);
If should be:
HTML Code:
$statscache['topposterpercent'] = round(100 * ($topposter[posts] / $totalposts), 2);
Second of all, if you have read the thread, you would see that this only works on small boards. On bigger boards you will get something like 15,300 % (your number would be different, but you get the idea) with your code.
And third, you are only counting replies this way, so you should call it Top Replier.
Do what you want, but the code will come out of it in the next update. It's not worth messing with anymore.