Average Years of Service for Members of the Senate and House of Representatives, 1st - 111th Congresses

The average tenure of Members of the Senate and House of Representatives at the beginning of each Congress has varied substantially since 1789. The purpose of this report is to provide a Congress-by-Congress summary of the average years of service for Senators and Representatives for the First through the 111th Congresses. The report contains a brief summary of some of the explanations by political scientists and others for the various changes in the average years of service