At a time when major religious groups around the United States are experiencing significant declines in membership, The Church of Jesus Christ of Latter-day Saints continues to grow substantially, according to the 2010 decennial U.S. Religion Census released today by the Association of Statisticians of American Religious Bodies.
The findings, released today in Chicago during the annual meetings of the Associated Church Press, show that while Catholic churches reported a 5 percent decline in membership during the decade that ended in 2010 and mainline Christian denominations reported a 12.8 percent decline during the same time period, the LDS Church reported growth of 45.5 percent.
The number of adherents to the Muslim faith in the United States grew by 66.7 percent.
The U.S. Religion Census includes county-level data drawn from congregations for 236 U.S. religious bodies, according to Scott Thumma of the Hartford Seminary's Institute for Religion Research and one of the leaders of the ASARB project. The numbers are based on membership reports from the religious bodies, as opposed to public opinion surveys that speak to individuals who identify themselves as members of one denomination or another.
Because the Religion Census charts growth on a county-by-county basis, it not only shows the overall growth rates of religions in America, but it also shows where that growth (or decline) is taking place. For example, while evangelical Christian churches have grown by only 1.7 percent overall, they have experienced significant growth in the New York City metropolitan area (13 percent) and in metropolitan areas of more than 5 million people (12.3 percent).
In other words, says Dr. Marie Cornwall, a professor of sociology at BYU, evangelicals are not growing as much as they are migrating to big cities.
"Coupled with the declining number of Catholic and mainline Christian adherents in big cities, the movement of evangelicals toward metropolitan areas has given them a presence — and political clout — in major metropolitan areas that they've never had before," Cornwall said.
While those numbers coming out of the 2010 Religion Census report are interesting, Cornwall said others should be taken with a grain of salt — or at least a high degree of understanding. She says that is especially true of the numbers relating to LDS Church growth.
"The LDS Church is very aggressive in the way that (it tracks) church membership — much more so than most other religious groups," said Cornwall, who specializes in the scientific study of religion. "And they don't drop people from their membership lists if they stop attending, or even if they join another church. People's names remain on LDS lists even when those people would no longer identify themselves as Mormons."
The other factor Cornwall says should be taken into account for both the Mormon and Muslim numbers is that the LDS and Muslim presence was relatively small in 2000, so any kind of meaningful growth can look huge in terms of percentages.
By way of illustration, Cornwall referred to the Religion Census numbers that show that the LDS Church experienced growth by more than 80 percent in the New York City metropolitan area during the past decade.
"But we didn't have very many Mormons living in the New York metro area in 2000, so any growth at all is going to seem really inflated," she said. "It's just difficult to compare populations in that way."
But Thumma pointed out that "nationally, The Church of Jesus Christ of Latter-day Saints gained nearly 2 million adherents over the past 10 years, far and away the largest gain reported by any group."
"The Muslim adherent count grew by over 1 million, making it the next largest in gains," Thumma continued. "In seven states — Florida, Illinois, Michigan, New Jersey, New York, Texas, Virginia and Tennessee — Muslim gains outpaced those of any Christian group."
Assemblies of God, Seventh-Day Adventists and Church of God (Cleveland, Tennessee) all reported increased of at least 100,000 adherents as well, Thumma said.
Thumma also noted that in 30 states, the LDS Church showed the largest gains of any Christian group, while Catholics showed the largest gains in 11 states, Assemblies of God in three states and six other groups each showed the largest gain in one state, including the District of Columbia.
For Cornwall, the most interesting LDS data in the Religion Census is seen while looking at the membership penetration map and seeing where the church is not growing.
"There are areas in the heartland of America where there has been an LDS presence for a long, long time, but we just don't seem to be growing much," she observed. "We've never really appealed to the blue-collar industrial demographic. These are the same people that Mitt Romney can't seem to impress. Why is that? I think that's something the church is probably taking a good long look at."