(CNN) -- Why not use those last few vacation days? Given an average of 14 annual vacation days, Americans left four days on the table over the past year, according to Expedia.com's 13th annual vacation deprivation study. That's twice as many as the previous year. "No one retires wishing they'd spent more time at their desk," said John Morrey, Expedia's vice president and general manager, in a statement. "There are countless reasons that vacation days go unused -- failure to plan, worry, forgetfulness, you name it. But rested employees are more productive employees, so taking regular vacations may well help the company more than failing to do so."
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Americans will not use four vacation days this year, study says
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Workers worldwide get an average of 20 vacation days
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Workers in France get 30 days and use all of them
The @placeholder top the scale in vacation days, getting 30 off each year and -- get this -- taking all of them.