In an effort to minimize employee-absence costs, more employers are dumping traditional absence policies in favor of paid time-off (PTO) plans. Such plans lump together time-off benefits (sick days, vacation days, personal days, etc.) into one leave bank. Last year, 42 percent of companies surveyed by Mercer Human Resource consulting used PTO plans, up from 30 percent in 2000. Plus, the percentage of employers that give employees the opportunity to buy and sell vacation days rose from 15 percent in 2000 to 24 percent last year. Young workers are often willing to buy more vacation time, while older workers often cash in extra time-off benefits.