5 or 6 weeks ago we deleted members that had not posted a month after registering in order to free up those usernames and increase performance.
Those members with zero posts are not included when calculating the memebrs total on the main page of your forum so the decrease will only be visible on the members page.
Thanks for the response Pad, I think the deletions should be done on the basis of who has not VISITED within a month. My site is features technical and operational issues that many lurkers come by and read about. lso, the e-mail addresses of the membership database was valuable. I used it to mail out questions / surveys to those who joined the list and later report back the results to all. thanks You must be logged in to see this link.
I haven't checked it but I don't think email is sent to those people who haven't posted.
It might be an idea to to set up a forum for lurkers to post at least one topic (even a test message) so as to ensure that they don't get deleted ever.