“This observation may go some way to explaining why a Finnish study found that single women recovered better from heart attacks than married women – particularly when put alongside a University of Michigan study which found that husbands create an extra seven hours o housework a week for women. An Australian study similarly found that housework time is most equal by gender for single men and women; when women start to cohabit, 'their housework time goes up while men's goes down, regardless of their employment status.”