Initial idea was to divide users into 3 groups: those who wrote 1 post, then group for 2-9 posts and 3rd for all that made 10+ posts. Does that make sense to you?
I like DdmrDdmr's way better. Since it's a yearly overview, 10 posts can't really be a number where you would consider someone to be an active poster. I would consider someone that makes a minimum of 10 posts per month in their local as a regular local board poster. Those should belong to the top category in my opinion. If we multiply that by 12, we get at least 120 posts a year to get into the big boys club. But it's not the same thing to write 120 posts in an active local such as the Russian or German, as it is in one that rarely gets much attention or only has a local thread, for example.