sex

"The 19th Amendment unleashed the untapped potential of half of the United States."

- Warren Buffett [born 1930]

women are 70% of the world's poor

“Women do two-thirds of the world’s work, receive 10 percent of the world’s income and own 1 percent of the means of production.”
— Richard H. Robbins, Global Problems and the Culture of Capitalism, (Allyn and Bacon, 1999), p. 354

Image source here.

An earlier reference to women's rights here.