Leaving Congress: House of Representatives and Senate Departures Data Since 1989 [September 24, 2010] [open pdf - 131KB]
From the Document: "Members of Congress leave the House or Senate for a variety of reasons; these may include resignation, death, or chamber action during a Congress, and retirement, electoral defeat, or pursuit of another office at the end of a Congress. In the 101st Congress (1989-1990) through September 2010 of the 111th Congress (2009-2010), on average, two Senators and eight Members of the House of Representatives have left before the conclusion of a Congress. Over the same period, on average, 10 Senators and 55 Members of the House left Congress upon expiration of their terms of office. These figures include those Members who have announced an intention to retire at the completion of the 111th Congress. The data provided here may offer insight concerning the turnover of membership in each chamber, but any such conclusions should be drawn with care, as there appears to be no pattern to Member departures. This may be due in part to the individualized nature of congressional careers, which might include numerous events or actions that could affect Members' decisions to end their congressional service. This report will be updated at the conclusion of the 111th Congress. Detailed information regarding 111th Congress departures is available at http://crs.gov/resources/Pages/ Congress_111_departures.aspx."
CRS Report for Congress, R41428
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