U.S. Senator tenure
January 16, 2010
The chart below shows the maximum (solid line), average (circles) and median (horizontal bars) of the distribution of tenures of U.S. senators serving at each year since the establishment of the body.
Over the last 200 years all three indicators of tenure length have been increasing steadily, approximately doubling every 100 years. There are now 52 senators with tenure of ten years or more, and two senators, Robert Byrd and Daniel Inouye, with tenure of about 50 years.
The chart was created using a table that I prepared based on the chronological list of senators available on the senate website. There may be some slight inaccuracies in the table, but I believe that on the whole the data is valid.