438 million.
That's the estimated number of vacation days Americans failed to take in 2007. Psychologists, demographers and others say we pass over time off for many reasons - everything from an entrenched Puritan work ethic, to fear of being seen as reckless slackers relaxing while the economy burns, to simply squirreling away time for days when we're stuck at home awaiting a repair call.
The figure for time left behind comes from Harris Interactive, the polling and research group, which for seven years has examined trends in unused vacation days for Expedia.com., the Internet travel booker. Expedia, along with just about every other travel-related business, overlays the findings onto the bottom line: If people aren't taking vacation days, they're not taking vacations.