Nearly 57 percent of Americans had unused vacation time by the end of 2011 -- 11 days on average -- forgoing 70 percent of their allotted vacation time, said a survey by Harris Interactive for JetBlue.
Financial information company Sageworks shows profits-per-employee are at a 10-year high.
"We don't have the exact information on why profits increased, but I think it's safe to say it's a combination of people spending more time at work and technological advancements," said Libby Bierman, a Sageworks analyst.
CNNMoney reported as companies scale back on staff due to the recession, more employees find themselves with larger workloads.
"I worry that if I'm gone for an extended vacation, the work won't get done and I'll come back to a huge pileup of projects," said Kyra Mancine, a catalog copywriter in Rochester, N.Y.
"I hate coming back to hundreds of e-mails," she added.