These surveys ask people how they identify their religious beliefs or what religious groups they are affiliated with. Answers depend upon what options they are given and how many people are surveyed. Results vary widely. For example, people who say they are Christian may be then given a list of denominations to choose among, or they may be given categories that include such terms as evangelical or Pentecostal. Some, such as the ARIS survey, ask people questions over the phone, while others, such as the Glenmary survey, gather data from religious groups. Each has its strengths and shortcomings, and most journalists find some surveys’ categories to be more trustworthy than others. In addition, some religious groups-Jews, Catholics and Baptists, for example-keep careful track of their own numbers.
THE 2001 AMERICAN RELIGIOUS IDENTIFICATION SURVEY by the Graduate Center of the City University of New York was a telephone survey of 50,281 people about religious identification and affiliation. The ARIS Web site includes data from a comparable 1990 survey.
FAITH COMMUNITIES TODAY was a 2000 survey of 14,000 U.S. congregations of different faiths by the Hartford Institute for Religion Research at Hartford Seminary. Reports continue to be issued based on ongoing research.
RELIGIOUS CONGREGATIONS & MEMBERSHIP IN THE UNITED STATES: 2000, a survey by Glenmary Research Center, presents data reported by 149 religious bodies that participated in a study sponsored by the Association of Statisticians of American Religious Bodies. The study is conducted every 10 years, and 2000 was the first year non-Christian groups were included. Some data is available free on the Web; the whole survey is available for purchase.
THE 2001 NATIONAL JEWISH POPULATION SURVEY, prepared by the United Jewish Communities, surveys about characteristics of Jews and Jewish life.
THE NATIONAL CONGREGATIONS STUDY was conducted in conjunction with the 1998 General Social Survey and included data about a representative sample of religious congregations. A new study is under way in 2006.
ADHERENTS.COM collects national and international religion surveys from many sources and meshes them into responses to questions about numbers that journalists often ask.
THE ASSOCIATION OF RELIGION DATA ARCHIVES posts a variety of surveys, reports and maps on religion.