This is how many hours you should really be working

Finally, a data-backed answer to an age-old question.

Have you ever wondered about the optimal number of hours to work per week?

Perhaps you are one of those people who brags about your 70-hour workweek, or maybe you are on the other end of the spectrum chasing the 4-hour workweek dream.

Who really has it right, anyway?

It turns out that the number of hours you work affects not only your productivity but also your happiness and perception of how much time you have.

And we currently have some room for improvement.

An estimated 40% of U.S. employees regularly work more than 50 hours a week, with 20% clocking in over 60 hours.

But those people are doing themselves (and their employers) a disservice.

Research shows that productivity falls sharply after 50 hours per week, and drops off a cliff after 55 hours. Additionally, not taking at least one full day off per week (e.g. Sunday) leads to lower hourly output overall.

From a productivity standpoint you shouldn’t go above 50 hours, but to cut down on stress you’d be wise to work even less.

The hours you work and your stress levels

It is no secret that we are busier and more connected than ever, often bouncing from one obligation to the next. This non-stop lifestyle has resulted in 48 percent of working adults feeling rushed for time, and 52 percent feeling significant stress as a result.

Time management expert Laura Vanderkam conducted a study to determine how the number of hours you work affects how much time you think you have.

Of the 900 people included in the study, the average person worked 8.3 hours per day. And the results showed that there was only a one hour difference between the people who felt like they had a lot of time and those who felt time-pressured. Those who felt like they had the least time overall worked 8.6 hours, whereas those who felt like they had the most time worked just one hour less (7.6 hours).

So to not feel starved for time, aim for a 7.6 hour work day. That would equate to a 38-hour workweek.

Work hours and happiness

A 38-hour workweek is remarkably similar to the number of hours worked in Denmark, consistently one of the world’s happiest countries (Denmark has placed among the top 3 happiest countries on the World Happiness Report in each of the last 8 years). People in Denmark work hard but rarely put in more than 37 hours a week, often leaving the office by 4 or 5pm. Other Scandinavian countries enjoy a similar work-life balance, and similar happiness rankings.

Happiness expert Dan Buettner takes it even a step further. Buettner has reviewed the research on more than 20 million people worldwide through the Gallup-Sharecare Well-Being Index, and has conducted extensive on-the-ground research in the world’s happiest countries. “When it comes to your work, try to work part-time, 30–35 hours a week,” he said.

Buettner also recommends taking six weeks of vacation per year, which is the optimal amount for happiness. If that isn’t possible, he says at the very least you should use all of your allotted vacation time and keep negotiating for more until you’re getting 6 weeks.

Unfortunately, Americans are not taking half of their vacation days, and two-thirds of Americans report working even when they are on vacation. Perhaps it’s no surprise that the US is down at #19 in the World Happiness Report (its worst ranking ever).

Maybe 30 work hours per week and six weeks of vacation is not practical for you. But that’s okay.

If you want to achieve the perfect blend of productivity, happiness, and time affluence, a more realistic goal is to work slightly below 40 hours per week.

The research shows that even shaving an hour or two off of the standard 40-hour workweek can have huge benefits, both at work and at home.

Less than 10% of workers are able to achieve that schedule. A good goal is to be one of those people.

Here’s to the 38-hour workweek!

This article first appeared on Atlassian.