Your friends don't like using their vacation days to celebrate your wedding

Americans spend 35% of their vacation days on other peoples' holidays — and a majority of them would rather spend the days on themselves, according to a new survey.

Only a fifth of respondents said they were “okay with using earned vacation time for other people's events.”

Americans already take less vacation than other developed nations. Vacation can even cause burnout, as nearly a fourth of employees find it harder to work when their coworkers take a break.

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In most cases, your close friends will opt to take a day or two off work to celebrate your bachelorette weekend — but they may not be happy about it.

In fact, Americans spend about 35% of their time off to celebrate other peoples' milestones, according to a new survey from London-based research firm Mortar for the travel company Flash Pack.

The survey found Americans average 10 vacation days a year, if provided by private companies (as the US is the only wealthy nation that does not guarantee days off). Of those 10 days, people spend 3.5 of them going to other peoples' weddings, birthdays, baby showers — pretty much any planned event that's not their own.

The survey comprised of 1,000 responses from men and women of all ages, income brackets, and US regions.

Millennials, in particular, give up more vacation days for other people — 61% of people ages 25 to 44 said they attended up to 10 local weddings in the last three years.

While spending time with loved ones seems like a valuable time commitment, 80% of all the people surveyed said they would rather spend their days off on themselves. Only a fifth of respondents said they were “okay with using earned vacation time for other people's events.”

“In a life that's already bursting at the seams, you're frittering away all your spare time and money on other people's dream,” Flash Pack co-founder Lee Thompson said in a statement.

Vacationing in America is proving to be more stressful than one would expect. Americans are notoriously bad at taking vacation when compared to other developed nations: a recent survey by pollster Gallup found three in 10 workers did not go on vacation in 2017.

Vacation can even cause stress. A survey conducted by Business Insider and LinkedIn recently found that 23% of professionals feel burned out when their coworkers are on vacation.

And since the US does not guarantee vacation, some employees have to choose between a day off and a paycheck: 25% of private companies do not give paid vacation, according to the Bureau of Labor Statistics. For workers in the “gig economy” who are treated like independent contractors, they have even fewer options for time off.