We recently made some changes to the way the reputation points decay on Forrst, and a lot of you have obviously noticed. The short of it is, every day, you lose all points that are over thirty days old. Everyone Does.
What this does is level the playing field for everyone, and encourages constant activity from you to keep your reputation up. (Foursquare recently did the same thing with mayorships).
Your old points always decayed, but at a much slower rate. So slow in fact, that it would take the old algorithm two weeks to process the number of Reputation Actions that happened on any given day. There was no way for the processing to ever catch up.
So, the reason that we made this drastic decision to cut out your old points completely, is because several of the “top 20” users were so far ahead of others no one could catch up, and some of these “top 20” users had been inactive for weeks.
So, while it looks like your points are just falling off, so are everyone else’s, and the change of your actual reputation percentile (which is what we care about internally) should be more representative of your actual activity on the site.
If you have any questions about these changes, or anything else regarding engineering at Forrst, feel free to email zack at forrst dot com