CBS Local– To some, the notion of unused vacation days is borderline inconceivable. But it’s not a rare phenomenon for many to leave days off on the table each year as 54 percent of American workers fail to use all of their vacation days.

How does it vary across the country?

Thanks to the folks at Project Time Off, we know which workers from which cities and states are leaving vacation days on the table.

Washington D.C. is the city that ends the year with the most unused vacation time, mostly due to the higher percentage of government workers in the capital than anywhere else. Government workers are the second most likely to use less than their full vacation allotment, just behind those in education.

Second for cities is San Francisco, the heart of Silicon Valley, followed by Tampa Bay in third.

As far as states go, the highest percentage of workers who use less than their allotted time off is Idaho, with 74 percent of those employed doing so. Second is New Hampshire and third is Alaska, where the cost of vacation is cited as a reason many opt not to take the time off.

On the other end of the spectrum are the cities that take full advantage of vacation days, with Pittsburgh being first on that list followed by Phoenix and Orlando.