Congressional Statistics play an important role in political science. I have often used a book which was regularly produced called "Vital Statistics on Congress". Unfortunately buying the book on a regular basis was an expensive proposition (and fills up the shelves!). It is no longer produced in book format. Brookings Governance Studies recently released an updated version - which is downloadable for free. I downloaded the 8 chapters onto my iPad, then opened each of them in "iBooks".
Click here to access the free download.
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The Eight Chapters are-
1 Demographics of members of Congress
2 Congressional Elections
3 Campaign finance in Congressional Elections
4 Congressional committee data
5 Congressional staff and operating expenses
6 Legislative productivity in Congress and Congressional workload
7 Congressional action on the federal budget
8 Political polarisation in Congress and changing voting attitudes