The 2010 U.S. Religion Census: Religious Congregations & Membership Study (RCMS) is a county-by-county enumeration of religious bodies in the US. It is an update of the 1952, 1971, 1980, 1990, and 2000 studies originally done by the National Council of Churches and the Glenmary Research Center. Since 1990, the Association of Statisticians of American Religious Bodies (ASARB) has sponsored the studies.
The ARIS (American Religious Identification Survey) time series tracks changes in the religious loyalties of the American public. It comprises a set of three large replicate, representative, national surveys of adults in the continental U.S.A. (48 states & DC) in 1990, 2001 and 2008.
The Pew Forum on Religion & Public Life, launched in 2001, seeks to promote a deeper understanding of issues at the intersection of religion and public affairs. Based in Washington, D.C., the Forum is a project of the Pew Research Center, a nonpartisan "fact tank" that provides information on the issues, attitudes and trends shaping America and the world.
The Pew Forum on Religion & Public Life details statistics on religion in America and explores the shifts taking place in the U.S. religious landscape. Based on interviews with more than 35,000 Americans age 18 and older, the U.S. Religious Landscape Survey finds that religious affiliation in the U.S. is both very diverse and extremely fluid.