Even though they earn the least amount of vacation days, millennial workers are the generation most likely to forfeit time off, according to a new study from Project: Time Off. Findings from “The Work Martyr’s Cautionary Tale: How the Millennial Experience Will Define America’s Vacation Culture” suggest members of Generation Y neglect vacation days because they experience more fear and guilt about taking time away from the office than any other age bracket.

“The entitled millennial narrative is dead wrong when it comes to vacation,” says Katie Denis, report author and senior director of Project: Time Off. “As the largest generation in the workforce, one that is now stepping into management, millennials are developing vacation attitudes that will define and negatively affect America’s work culture. The circumstances of the millennial experience—the Great Recession and its aftershocks, growing student debt and an always-connected lifestyle—have created a perfect storm for their work martyr behavior.”

Project Time: Off defines work martyrs as employees who skip vacation to show complete dedication to their job. They are often worried they will be perceived as replaceable, feel guilty for using time off and believe they alone can do the job. The survey, which took place January 20-February 16, was based on 5,641 online responses from a random sample of American workers who put in at least 35 hours per week and receive paid time off.

Millennials were found to be more insecure about their employment compared to other generations. They are at least twice as likely to find taking time off difficult because they don’t want to lose consideration for a raise or promotion; don’t want others to think they are replaceable; and want to show complete dedication, among other reasons.

According to the report, more than a quarter of millennials are in management roles already—a number that will rise as baby boomers leave the workforce. Nearly half of managers belonging to Generation Y said that company pressure prevents them from approving time off requests for their direct reports, compared to just 34 percent of Generation X and 37 percent of baby boomers who admitted to the same. In addition, almost half of millennials think it’s beneficial to be seen as a work martyr by their boss, while only 32 percent of older generations felt the same way.

“There are larger implications for the workforce when people don’t take vacation,” Denis added. “Time off is essential to employee productivity, creativity, and overall performance. Businesses need to recognize the power of time off and work toward creating a positive vacation culture.”

Reasons Time Off Is Left On The Table Millennials Boomers
Don’t want to lose consideration for raise or promotion 26 percent 9 percent
Don’t want others to think I am replaceable 27 percent 11 percent
Want to show complete dedication to the company and my job 30 percent 15 percent
Feel guilty using my paid time off 27 percent 12 percent
Afraid of what my boss might think 23 percent 10 percent