How much is one day of vacation worth to you? More companies are asking workers to make that calculation with programs that allow them to cash in paid time off (PTO) for other types of benefits, such as a contribution to a retirement or education savings plan. In some cases, employees can donate their PTO to a colleague who needs it. The popularity of so-called PTO conversion or purchase programs is growing, according to a recent report , but experts said HR teams should be thoughtful about how