80%

There's a great segment on Foreign Exchange about gender inequality in Africa (the segment in question is in the final third of the show). Maria Metembe, who is the Minister for Ethics in Uganda, and has been involved in Ugandan politics for many years, lets us know that 80% of the food produced in Africa is produced by women, while almost none of the land is owned by women. Watch the rest of the interview--it's full of compelling facts, and she is quite a persuasive speaker.