Congress is constantly changing and is constantly in flux. In recent times, the American south and west have gained House seats according to demographic changes recorded by the census and includes more minorities and women although both groups are still underrepresented. While power balances among the different parts of government continue to change, the internal structure of Congress is important to understand along with its interactions with so-called "intermediary institutions" such as political parties, civic associations, interest groups, and the mass media.