I don't quite understand the question, but I can say that this function has not changed in a long time and will be working fine.
1) Make sure you do not have many websites that are tied with the same statistics.
2) ranks on buttons are "cached" so they are not real time rankings.
both of these issues really only affect small lists just getting started with test listings, once you have real memebrs with real statistics the ranks will work as expected.