In 2013, American employees forfeited 169 million days of paid time off that could not be rolled over, paid out or banked.  This resulted in employees losing $52.4 billion in benefits in 2013, according to a survey conducted for the U.S. Travel Association's Travel Effect Initiative.  While employees may make choices to forego using PTO to have more "face time" at work, research shows that this "face time" actually results in a 6.5% decrease in the likelihood that an employee will receive a raise or bonus in comparison to those employees who use all their vacation days.  While there is no positive correlation between working more and compensation increases, it is unsurprising that taking fewer and shorter vacations increases stress.  Indeed, workers who forego using eleven or more vacation days per year were 6% more likely to report being "very" or "extremely" stressed with their work lives in comparison to those employees who took all their PTO.  Source:  U.S. Travel Association