The studies found that the mistake rate in two intensive-care areas decreased when interns worked fewer hours.

VOA: special.2010.07.13

And for women who were driving or sitting for more than 60 hours, the rate of gallbladder removal was 132% higher than for active women.

BBC: Exercise reduces gallstone risk

Expressed in terms of flight hours, the accident rate is nearly identical.

ECONOMIST: Business travel

Federal Reserve already charges for Fed funds by the minute, and the Bank of Japan charges a flat rate every four hours.

ECONOMIST: Foreign-exchange settlement