Well, waaaaaaaay back in the 1990's I remember a recruiter and I were discussing the numbers behind the NDP's efforts to "balance things out" in Ontario..

In some sectors, businesses etc., the workforce is 95%+ male (we won't get into the ethnic/racial aspect)...the general turnover in the workforce (at the time) was something like 4% (it may be higher now, but less at larger organizations), and factoring in the fact that women leave jobs as well, you would likely have around a decade and a half, of hiring women 100% of the time, in order to balance the apparent workforce in a given organisation..and quite likely over 2 decades... 

Left unsaid of course, is what you would have to do in teaching, nursing, and other well-paying professions to balance it the other way....not that that would ever be on the agenda, or course...

All of it boggles the mind......