Chrissa1
If you click on "see all members" in the Classmates page you can filter by years, but I suspect that at the last change people were asked to confirm they wished to retain membership, and that's why many are now missing (because they didn't bother).
I've only used it intermittently, but it has put me in touch with a very good friend who lives 45 minutes drive away, and had done for 20+ years. We now meet every few weeks, and our wives get on even better than we do!