I just rooted out a graph of IESG size over a number of years
that I created for a similar discussion 7 years ago.
As far as I know, today's numbers are identical to 2006, since
no Areas have been created or deleted and we have two ADs/Area.
http://www.cs.auckland.ac.nz/~brian/IESGsize.pdf
At that time about 125 WGs were chartered. Today we still have
about 125 WGs.
Regards
Brian