If you've made a lot of posts in a thread and it gets trashed then your post count will go down. Don't post in unsubstantial threads that are liable to be deleted if you're worried about this.
Now I know what had happen to my post count that decreases instead of the count to increase. Some time in August which almost made me lost my weekly pay from the campaign that I was promoting at that time and another just happen this week. Many thanks hilariousandco for your reply to this guy threat.