Vital Statistics on Congress

Vital Statistics on Congress, first published in 1980, long ago became the go-to source of impartial data on the United States Congress. Vital Statistics’ purpose is to collect and provide useful data on America’s first branch of government, including data on the composition of its membership, its formal procedure (such as the use of the filibuster), informal norms, party structure, and staff. With some chapters of data dating back nearly 100 years, Vital Statistics also documents how Congress has changed over time, illustrating, for example, the increasing polarization of Congress and the diversifying demographics of those who are elected to serve.

Click here to access the Vital Statistics data tables »

Vital Statistics began as a joint effort undertaken by Thomas E. Mann of Brookings and Norman J. Ornstein of the American Enterprise Institute, in collaboration with Michael Malbin of the Campaign Finance Institute. The datasets were published in print until 2013 when the project migrated online for the first time. This year, Brookings’ Molly E. Reynolds spearheaded Vital Statistics’ most recent update. The eight chapters below contain more than 90 tables of data which were collected through the years of this project and updated most recently in July 2018.

Whether you are new to Vital Statistics or an old Vital Statistics hand, here are a few things to know about the most recent update:

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The January 2017 update to Vital Statistics was overseen by Molly Reynolds. Curtlyn Kramer provided principal research support with additional assistance from Nick Zeppos, Emma Tatem, and Tanner Lockhead. Data collection for Chapter 3 was performed by Michael Malbin, Brendan Glavin, and the team at the Campaign Finance Institute. Work on the January 2017 update was informed considerably by the work of all past Vital Statistics authors and contributors, especially Thomas E. Mann, Norman J. Ornstein, Raffaela Wakeman, Andrew Rugg, and countless research assistants and interns at Brookings and AEI.