And it's cost the U.S. economy $223 billion.
Stressed man
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It’s happened again: Americans are leaving millions of unused vacation days on the table—658 million of them to be exact. According to a new study by Project: Time Off, the average U.S. worker took only 16.2 days of paid time off in 2015 and 55% of the 5,600 people surveyed didn’t use all of their vacation time.

The new survey reveals that more people are taking less time off. From 1976 to 2000, the average number of days workers took off was 20, almost four more than last year. And 2014’s study showed only 42% of Americans had unused days, making this year the first time since the survey began that a majority of workers aren’t using all their paid time off.

And out of those 658 million unused vacation days, 222 million of them will be lost entirely because they couldn’t be rolled over, paid out, or used for any other benefit.

All of this equates to about $61.4 billion in lost benefits for workers, and some $223 billion in lost travel-related spending in the United States.

While the study revealed more and more Americans aren’t taking time off, it also exposed that it’s not because they don’t want to. According to the study, 80% of employees said that would take more vacation if they felt supported and encourages by their bosses. Still, 65% of employees said they are often discouraged from taking time off.

"The culture of silence has created a vacuum, and American workers have filled that vacuum with the pressure they put on themselves," study author and senior director of Project: Time Off, Katie Denis, writes. "The single-most important step workers can take is to plan their time off in advance."