Americans once worked 100 hours a week, six days in a row. Then, in 1940, came the five-day workweek.

Now labor unions are making the case for even less work: dropping days worked down to four.

That’s one of the changes unions are proposing as part of their vision for the future of work, which is outlined in a report to be released Friday by the AFL-CIO, the largest federation of labor unions in the US. (Disclosure: I am a member of the Writers Guild of America East, which is part of the AFL-CIO.) The report, which was shared in advance with Vox, focuses on finding ways to make sure workers can best benefit from automation and other technological changes.

As technology makes workers more productive, unions argue, why not give them three-day weekends? Not 40 hours compressed into four days. Labor unions are proposing a 32-hour workweek, with employees earning no less than they did before.

It may seem radical, a change that businesses would resist. But Richard Trumka, head of the AFL-CIO, assures me it’s not.

“We are very serious about this,” Trumka told me. “If we’re going to free up jobs for more people, then we have to go there.”

Trumka said some unions are already bargaining for shorter workweeks in the construction industry and health care sector but that it needs to happen nationwide. Labor unions and workers did pressure Congress to amend the Fair Labor Standards Act during World War II, which limited full-time work to 40 hours a week, plus overtime pay. Nothing is impossible.

According to researchers, shortening the workweek would have two benefits: It would redistribute work hours to the underemployed and it would actually make workers more productive. Maybe it’s not such a wild idea after all.

Millions of workers need more hours

The idea of a four-day workweek isn’t new. Juliet Schor, an economics professor at Boston College, suggested shorter workweeks in her 1993 book The Overworked American. Schor argued that Americans are working longer hours than they did before World War II but they’re not seeing the payoff. Her proposal for shorter workweeks was considered “unrealistic” by critics.

w the idea is getting more attention as academics wonder what will happen if robots end up eliminating too many jobs, especially those in the retail and restaurant industries. Unions say a four-day workweek is a good way to redistribute work hours to those who need them while giving other workers a break.

Even with record-low unemployment right now, millions of people are working part-time jobs when they would rather get full-time work, or at least more hours. The number of people in that group has been mostly shrinking in the US but increased to 4.4 million workers in August.

And yet, those Americans working full-time jobs are still working more hours than anyone else in the developed world without seeing much of a payoff. Americans worked 106 more hours in 2018 than Japanese workers, 248 more hours than British workers, and 423 more than Germans, according to the Organization for Economic Cooperation and Development.

But that doesn’t mean American businesses are getting more work out of their employees who clock more hours. Having a set schedule to sit at a desk or show up on-site does not equate to efficiency or money well spent. It often leads to frustrated, burnt-out employees. Workers everywhere want more time off.

A third of workers (about 40 percent in the US) say they would prefer a four-day week, according to the Workforce Institute at Kronos, which surveyed workers in the United States, Mexico, Canada, Australia, New Zealand, the UK, France, and Germany. Another 20 percent said they wanted a three-day week.

Scandinavian countries seem to have it all figured out. In the Netherlands, workers clock in about 29 hours a week, earning an average of $47,000 a year. That exactly what American workers earn, on average, and yet people are working at least five hours more each week in the US.

It’s not like these workers are being inefficient or lazy; research suggests shorter workweeks make employees more productive.

What the research says

The five-day workweek might actually be counterproductive. The idea that putting in long hours is better for a company’s bottom line is a myth, according to the International Labour Organization at the United Nations.

“In fact, longer hours of work are generally associated with lower unit labour productivity, while shorter hours of work are linked with higher productivity,” the group concluded in a 2018 research paper.

A study in the American Journal of Epidemiology found that those who worked 55 hours per week performed worse on certain mental tasks than those who worked 40 hours a week.

Psychology professor Anders Ericsson and his colleagues at Florida State University have studied top performers in sports, entertainment, and chess. In each of these fields, Ericsson discovered that the best performers normally practiced in uninterrupted sessions that last no more than 90 minutes. They concluded that top performers rarely work more than four-and-a-half hours a day.

But this isn’t just relative to the arts. Businesses have also been experimenting with shorter work hours, and the results look promising.

Last year, a New Zealand firm asked researchers to study what would happen if the company let its employees work 32 hours a week while being paid for five full days, according to the New York Times.

The will and trust management company, Perpetual Guardian, said the change actually boosted productivity among its 240 employees. They spent more time with their families, exercising, and cooking. Those employees reported a 24 percent improvement in their work-life balance. Supervisors said the staff work attendance and creativity improved too.

The experiment suggests that simply giving workers more time to enjoy their lives makes them better workers.

Other proposals in the report

A four-day workweek is just one idea the AFL-CIO is proposing to make the future of work better for workers. The federation’s report also recommends paid vacation and sick days for all workers, not just salaried employees.

Another key priority is to involve workers and labor unions in tech research, which is often funded by taxpayers. For example, Trumka said the head of a nurse’s union met with robotics students at Carnegie Mellon University, where they are developing a robotic arm to help feed hospital patients. The nurses were able to give input on what kind of movements are needed to make sure it works properly.

The federation also plans to launch a technology institute, in which unions will partner with universities like Carnegie Mellon so workers can shape how technology is developed.

“We don’t view tech as good or evil,” he said. “It’s about how it’s ultimately deployed.” The point is to make sure that technology is used to improve work, not replace workers.

In the meantime, three-day weekends would be nice.