Europeans have a reputation for taking extra long holidays during summer.

In Norway, the term "fellesferie" refers to two or three weeks of vacation time workers collectively take in July — leaving businesses closed or operating on summer hours.

In the Netherlands, employees in the building industry take construction holidays called "bouwvak" for several weeks.

And until two years ago in France, a law required Parisian bakers to stagger their summer vacation time so enough bakeries stayed open for customers during the holidays.

It's an envious concept to many Americans — the United States is the only counry in the Organization for Economic Co-operation and Development that does not mandate paid vacation. Research shows many Americans who receive paid time off are afraid to take it because of workplace pressures. But it turns out the European vacation mindset could actually help boost productivity.

The European Union's Working Time Directive guarantees EU workers at least 20 paid vacation days per year, contrary to the United States, which does not have a statutory minimum annual leave requirement. Some European countries mandate additional time off: The U.K., France, Austria, Denmark, Finland, Luxembourg and Sweden all require 25 or more paid annual leave days, according to the OECD.

Data show more time off doesn't have to translate into lower productivity. Nine of the top 10 most productive countries in the OECD in 2015, measured by GDP per hour worked, were in Europe. The United States ranked sixth.