As they have throughout the nation's history, Americans see themselves today as a religious people, but their ties to churches, synagogues, mosques, and temples are in flux and continue to loosen.
A dramatic rise has taken place over the past decade in the proportion of residents who say they have "no religious preference," even while most of them continue to believe in God. This group doubled between 1990 and 2001 to an unprecedented 14 percent of the population, according to a 2001 survey.
Now, a recently released study of religious congregations the widest snapshot of American denominational ties ever completed confirms this and other key trends:
Socially conservative denominations grew faster between 1990 and 2000 than others, with mainline Protestant churches continuing to decline.
The overall increase in religious affiliation did not keep pace with the rate of US population growth (8.8 percent compared to 13.2 percent).
Almost half of Americans are not claimed by any religious group.
Some of the rapid increases in adherents are linked to immigration, which is reshaping Catholic and Protestant churches as well as smaller world faiths.
The recently released report "Religious Congregations and Membership in the United States: 2000" is the latest in a series of 10-year studies conducted at the same time as the US Census (which does not gather religious data). The study was sponsored by the Association of Statisticians of American Religious Bodies, and published by Glenmary Research Center (GRC), a Catholic group in Nashville, Tenn.
The report is not as reliable as a census since it is based on self-reported data from religious denominations, which have varying skills and approaches to data collection that often must be adjusted to be comparable. The 149 participating religious bodies reported more than 140 million adherents. For the first time, estimates were included for Muslims and Eastern religions as well as for Christians and Jews, although some Muslim groups have questioned the results.
And there are significant gaps: Some major African-American denominations, such as the African Methodist Episcopal Church, are not included; data for independent churches cover only those with more than 300 members; and some groups, such as Jehovah's Witnesses, declined to participate.
Still, it's the most comprehensive look at the religious landscape so far.
Only four of the 17 religious groups with more than a million adherents have increased faster than the US population (see chart on page 12).
The Church of Jesus Christ of Latter-day Saints which sends its young people out to recruit in the US and abroad grew most rapidly, by 19.3 percent, to 4.2 million. Its greatest support remains in Utah and surrounding states.
Evangelical groups next in line include the Christian Churches and Churches of Christ, at 18.6 percent, and Assemblies of God, the largest Pentecostal denomination, at 18.5 percent.
Pentecostals are known for their emphasis on "gifts of the Holy Spirit," including healing and speaking in tongues. According to church statistician Sherri Doty, the Assemblies of God expansion is due partly to growth in ethnic communities. "Hispanic churches grew by 29 percent and Hispanic adherents by 53 percent," she says.
The Catholic Church, which at 62 million is the country's largest denomination, grew by 16.2 percent. Immigration played a key role here as well, including Hispanics and Vietnamese, says Kenneth Sanchagrin, director of GRC.
Many Catholics have moved from the Northeast and Midwest to the South and Southwest. Dr. Sanchagrin sees migration to the South, a Baptist stronghold, as presenting challenges for ecumenical relations. Competition is also strong between Catholic and Evangelical churches for the allegiance of the mushrooming Hispanic community, which is expected to become one-fourth of the US population by 2050.
"Immigration and its impact on religion is a very important story for the coming decade," says Richard Alba, a sociologist at the State University of New York in Albany.
The increase in the largest Protestant denomination the Southern Baptist Convention (20 million), which puts a premium on proselytizing uncharacteristically fell well below the pace of US population growth. Some attribute the slide to internal controversies that developed after conservatives gained control of the denomination.
The 2000 report confirmed steep declines in some mainline Protestant memberships. The Presbyterian Church (USA) dropped by almost 12 percent over the decade, and the United Church of Christ by 15 percent. The United Methodist Church, the third largest US denomination at 10 million, lost 7 percent.
Non-Christian tallies present difficulties in making data comparable, researchers say. The Jewish estimate, for example, is based on ethnic, not religious affiliation, and encompasses secular Jews.
Neither Muslims nor Eastern religions are accustomed to the concept of membership at mosques or temples. The Muslim count of 1.6 million adherents is an estimate based on information from one-third of US mosques, and falls far below the 7 million usually claimed by Muslim organizations. Eastern religions accounted for 150,000 adherents.
Other findings of interest:
Northwesterners shy most from church affiliation. Just 31 percent of Oregonians and 32 percent of Washingtonians belong to religious groups, with Alaska residents at 34 percent.
Los Angeles is the most religiously diverse urban area, and Illinois the most religiously diverse state.
The United Methodist Church is the most widespread present in 96 percent of counties.
Though relatively small, the Salvation Army (415,000 adherents) reported the most rapid increase of all over the decade 225 percent.
Residents in metropolitan and nonmetro areas in the US show the same level of affiliation: 50 percent.
Yet many Americans identify with specific religions even though they have no formal connection to a place of worship. In the American Religious Identification Survey conducted by the City University of New York in 2001, 81 percent named a religious preference, and 75 percent said their outlook on life was more religious than secular.
Meanwhile, the proportion who classified themselvesas Christian dropped from 86 percent to 77 percent. And one-sixth said they had switched their religious affiliation.
But the steep rise to 14 percent of those who say they have "no religion" had little to do with religious skepticism, insist researchers at the University of California-Berkeley. (Only 1 percent were atheists or agnostics.) In an article in the American Sociological Review, Michael Hout and Claude Fischer point instead to demographic shifts and politics. Extended schooling and delayed parenthood were factors, they say, as was alienation of some moderates and liberals in response to the politicizing of religion in the 1990s.
For some, the huge "unclaimed" portion of Americans and the geographic and demographic shifts represent unsettling trends. Yet religious denominations reported $29 billion in contributions in 2001, vividly demonstrating "the robustness of American religious tradition," says Eileen Lindner, of the National Council of Churches.