Over its 224-year history, the United States Senate has seen a remarkable 299 sitting senators die in office, according to data from the body's website — nearly enough to populate three senates of their own. On average, that's one death every nine months.

The deadliest time to be a senator was early in the last century. Between 1900 and 1949, 130 sitting senators died — though many died while the Senate was out of session.

As might be expected, the earlier a state joined the union, the more sitting senators it has lost over its history. The death of Senator Frank Lautenberg is New Jersey's ninth such death. South Carolina, also one of the 13 original colonies, has lost 14 senators. The only states that have not had a senator die while in office are Utah and Arizona. Scroll over below for more.

The deadliest Congress was the 65th, spanning 1917 to 1919. Ten sitting senators died during that period.

The first senator to die in office was William Grayson of Virginia. His death, one year and eight days into his tenure, resulted in the loss of 3.8 percent of the 26-person legislative body.

Photo: The casket of President Reagan lies in state in the Capitol Rotunda. (AP)
Hat tip to Kenneth Chamberlain.