My graduating class, with just over 1000, was the largest class ever up to that date, and has since been passed only a few times.
With all that information as a prelude, I offer up this little tidbit of information found on the Association of Graduates (read, Alumni) web site:
As of the close of business on 10/06/2010, the Mid-Point of the Long Gray Line belongs to COL Terrence J. McKenrick Class of 1985. There are 48,069 living graduates.
The Oldest Living USMA Graduate is COL Thomas J. Wells USA (Retired), Class of 1928. He is 104 years old.
I'm very close to being in the upper half of all living graduates.