Taken from the Contento Index as a sample (anthologies, collections, magazines) and by author, NOT by publication count :-
http://www.philsp.com/homeville/MSF/0start.htm#TOC This is from 1990-2007 apparently.
With a little over 1% did not know due to initials only (and the odd name guess),
and over 600 people :-
Male 64%
Female 36%