Quick: who works longer overall? men or women?
If you add up the time spent working for money ("market work") and the time spent at home doing work that needs to be done (cooking, washing, etc.), it turns out that men and women spend about the same amount of time working ... in rich countries at least.
Don't know if there was a reporting bias there (did any respondents exaggerate, or shy away from revealing housework?) -- the paper's too full of social science jargon to tell.