Europeans are spending less time at work, and governments would like them to get back to the grindstone. That is the thrust of measures German, Dutch and British ministers have been examining to persuade part-timers to take on more hours, and full-timers to embrace overtime.

But the evidence suggests it will be an uphill battle — and that authorities worrying about a shrinking workforce would do better to help people who might otherwise not want a job at all to work a little.

Rising prosperity is the main reason the working week has shortened over time, as higher productivity and wages have allowed people to afford more leisure. In Germany, for example, it has roughly halved between 1870 and 2000. Across the OECD, people are working about 50 fewer hours each year on average than in 2010, at 1,752.