Where can I find statistics for the percentage of women voters from 1920 to present?

Question

I am researching for a term paper contrasting women who fought for the right to vote and those who were born with that right. My hypothesis is that the women of the 1920's who fought for that right were more likely to excersise that right than modern women. My findings so far show that 33% of eligible female voters voted in the 1920 Presidential election.

Answer 1

Try Emily's List. I thought the 1920 number was around 40%