Sure, but we're talking about white women, which make up about 33% of the population of the US. Are you arguing that it's ok that 79% of the publishing industry is white and 78% is female?
[1] http://www.npr.org/sections/thetwo-way/2014/11/21/365707391/...
I'm inclined to believe that there is no correct percentage and that even trying to simplify as you have is disingenuous and leads to simple but wrong explanations that ignore all sorts of contributory factors.
I'm a cis-male that identifies as agender, but I haven't seen any evidence that I'm under-represented in the publishing industry because my gender is discriminated against. That's an extraordinary claim and requires extraordinary evidence.
Furthermore, I'm curious to hear your thoughts on base rates and how they contribute to measurements of diversity?