Billionaire Carlos Slim speaks during a news conference in this 2013 file photo. Susana Gonzalez/Bloomberg
Billionaire Carlos Slim has proposed a different work week.  Susana Gonzalez/Bloomberg

You’re working too many days a week, says Mexican billionaire Carlos Slim.

Slim wants everyone to switch to a three-day work week. But there is a trade-off. With the shorter week, people would work for 11 hours a day, and for more years, until they are 70 or 75 years old, said Slim, who is 74, in a speech at a conference in Paraguay, according to the Financial Times.

“With three work days a week, we would have more time to relax; for quality of life. Having four days off would be very important to generate new entertainment activities and other ways of being occupied,” said Slim, who is the world’s second-richest person.

Workers at Telmex, the telecom company where Slim made his fortune, can retire before they are 50 years old. But Slim has given them options to stay on the job after they are 50, but for only four days a week.

Slim is not the first person to advocate a change to the typical 40-hour, five-day work week.  The Swedish city of Gothemburg has proposed experimenting with a six-hour work day by having one group of government workers work six hours a day, while another group works a normal eight-hour day. If the first group is found to be mentally and physically better off and more efficient in their work, then the city could consider extending the six-hour workday to other parts of civil service.

Another Swedish town, Kiruna, conducted a similar experiment with a six-hour work day but returned to the standard eight in 2005.

“Kiruna’s project showed good results,” said Mats Pilhem, a Swedish local politician who came up with the idea to shorten the work day in the town. “But it was too expensive for the municipality, the economic savings from reduced sick leaves etc went to the government – not back to Kiruna. It also lacked a proper evaluation of the results and effects of their experiment,” Pilhem told my colleague Adam Taylor in an e-mail.

American workplaces have remained on the standard 40-hour, five-day work week since 1938. Could Americans ever get to work four days a week instead?

Google CEO Larry Page recently suggested it, saying that “most people like working, but they’d also like to have more time with their family or to pursue their own interests.”

In 2008, Utah became the first state to mandate a four-day workweek for all state employees as a way to lower energy consumption. A year later, state planners found that in addition to the reduced energy use, there were unexpected boosts to productivity and worker satisfaction as well. But the state switched back to the traditional work week in 2011 when residents complained some state services weren’t available on Fridays.