Chan,
There are a lot of things that don't show up in the numbers, like the hours that I sleep with my head on my computer desk with the PM.com website on the screen, or where I use the PM.com screen as a home page or a night light

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More seriously, all the time that the Moderators spend keeping everything in order also mounts up over the years and is included in the numbers, in my case since sometime in 2004 when I first became a Moderator. All new member profiles are reviewed by the Moderators and I try to look at every new post to be sure that it is posted in the right board and, if not, to move it to a better place. The other day, as part of a new project, I reviewed and updated the NY Style board. That took me all day. Not long ago, Bill/SFNM and I were tearing our hair out (I have never seen a photo of the mysterious Bill but I assume he has hair) as the forum was being slammed by spammers outside of the U.S., often at night when everyone is asleep. Fortunately, Steve was able to take measures to stop the deluge. These are only a few of the things that go on behind the curtain that most members never notice. But without those monitoring efforts, the forum could end up in shambles, as almost happened recently at the PMQ Think Tank until the PMQ management intervened.
Moderators also tend to get more PMs than other members. I delete mine from time to time but over the years they have amounted to thousands in my case. I try wherever possible to have such members post their questions before the open forum, so that everyone can participate or benefit, but for the others I respond just as I would on the forum. All that time makes its way into the numbers too. Things were much easier when I first joined, when there were 142 members. Now we have over 10,800. Of course, not everyone posts but the numbers have been going up rapidly as people discover the forum.
Peter