But, according to a Post review of the history of Cabinet members, Hagel's tenure was not that far from the norm. On average, members of Cabinets have served 1,118 days between confirmation and resignation. Hagel's put in 635. Secretaries of Defense tend to have slightly shorter tenures, on average, but barely.
Of the 485 former members of Cabinets, though, Hagel has had the 157th shortest tenure -- putting him just into the one-third of members who have served most briefly. In fact, Hagel's already outlasted two Cabinet members that served under Obama: John Bryson, who served two-thirds of a year, and Hagel's predecessor, Leon Panetta, who served just over 600 days. And that's assuming Hagel were to leave today, which he won't. Another five days, and he's served longer than former Secretary of State Christian Herter.
Another Secretary of State is tied for the shortest tenure in the Cabinet. Elishu Washburne was appointed Secretary of State under President Ulysses S. Grant in 1869 -- and then got sick and resigned after 11 days. His tenure is matched by the exotically named Thomas McKean Thompson McKennan, who reluctantly agreed to be the country's second Interior Secretary and then resigned after less than two weeks.
There have been 13 Cabinet members whose tenures have lasted under 100 days; 75 who haven't made a full calendar year.
The longest-serving member, incidentally, was James Wilson, who served as Secretary of Agriculture under three presidents (McKinley, Roosevelt, and Taft), lasting over 5,800 days in the job. There's something about Agriculture which lends itself to longevity; it has the highest average length of tenure of any Cabinet position.
And, to close the loop, there are two members of Obama's Cabinet who have been in place since the very beginning (excluding the soon-to-resign Attorney General Eric Holder). One is Arne Duncan, the Secretary of Education, who's on the job since 2009. (Education secretaries have the second-longest average tenures.) The other is Tom Vilsack, Secretary of Agriculture.