You might see that your post count fluctuates a bit from time to time. There are legitimate reasons as to why that happens. Here is why..
1. To keep our community friendly, safe and helpful, we actively moderate our forums. As part of that process, we do delete threads that violate our forum rules. If you had participated in one such thread, that would reduce your post count.
2. Posts made in certain forums don't count towards post count. If we moved a thread from a forum where posts are counted to a forum where the posts aren't counted, your post count will get reduced as a result.
The above actions, doesn't immediately reduce your post count. Whenever we do database maintenance, our system goes back and recalculates the post count as a result of all such actions we took after the last database maintenance. So, you might see stable post count for a while and then a drop off whenever we do database maintenance.