(CNN) -- It has been described by some of the people who have held the job as an insignificant one, but it gets attention every four years when presidential candidates are choosing the other half of their ticket. Here's a by-the-numbers look at the vice presidency:
Who might run with Romney?
47 -- The number of vice presidents who have served the U.S. since 1789.
13 -- The number of Republican vice presidents since 1900.
10 -- The number of Democratic vice presidents since 1900.
Author looks to honor VPs' 'history of insignificance'
14 -- The number of vice presidents who became president of the United States. Eight of these were because of the death of the sitting president.
4 -- The number of vice presidents who went directly from that office to the presidency. They are John Adams, Thomas Jefferson, Martin Van Buren and George H.W. Bush. Acting as president of the Senate, each man was able to announce his own election to the presidency.
3 -- The number of vice presidents who, as president of the Senate, had to announce they'd lost the presidential election. They are John Breckinridge, Richard Nixon and Al Gore.
1 -- The number of vice presidents who became president, but did not go directly from one office to the other. Richard Nixon left the office of vice president in 1961 and was inaugurated as president in 1969.
2 -- The number of vice presidents who were not elected to the office. They are Gerald Ford and Nelson Rockefeller, both in the 1970s.
2 -- The number of vice presidents that resigned from office: John Calhoun and Spiro Agnew.
1967 -- The year that 25th Amendment was passed, clarifying what to do in the case of a presidential vacancy or disability.
3 -- The number of times that Section III of the 25th Amendment has been invoked -- in which the vice president becomes acting president. This happened in 1985, when President Ronald Reagan underwent surgery, and in 2002 and 2007, when President George W. Bush was sedated for medical procedures.
VP candidates face 'intimate examination'
3 -- The number of vice presidents who have won the Nobel Peace Prize. They are Theodore Roosevelt, Charles Dawes and Al Gore.
1 - Number of vice presidents accused of murder: Aaron Burr.
1 -- Number of vice presidents to take up arms against the United States government: John Breckinridge during the Civil War.