Could I give another very simple example of why the old equal-pay laws don't work? Under an equal-pay law, by and large you compared two jobs only to find out whether they were identical or not. For example, the cleaner who happens to be a lady—and I did work for the House of Commons for a while, so I know a little bit about the so-called cleaning women here—if they happened not to be having to carry a ladder, which the male workers might have to do, they couldn't be compared. So their incredible restrictions sound artificial, but you couldn't actually get at the work that was being done if there were any differences.
Under the current international rules that Mary mentioned earlier of equal pay for work of equal value, we can look at all the aspects of the work, and that's important to give people—employees and employers—the notion that we're being fair. So underlying “equal pay for work of equal value” is the notion of fairness. We look at all aspects of work, including stress, as you mentioned.