Mainline Protestant churches faced a decline in membership over the past year while membership in the Catholic, Mormon and Assemblies of God churches has grown, a report from the National Council of Churches (NCC) U.S.A said.
The NCC's 78th annual church Yearbook, which chronicles the 2009 growth trends of the 25 largest churches in the U.S., saw membership decline in nearly all major Protestant denominations, including the 16.2 million- member Southern Baptist Convention, and the 7.8 million-member United Methodist Church, whose memberships dropped by 0.24 percent and 0.98 percent, respectively.
Other churches who reported a decline in membership included the Evangelical Lutheran Church in America (ELCA), whose numbers fell 1.62 percent to 4,633,887 million members; the Episcopal Church (TEC), which dropped 2.81 percent to 2,057,292 members; and the American Baptist Churches in the U.S.A (ABCUSA), which fell 2 percent to 1,331,127 members.
The largest drop in membership was registered by the Presbyterian Church (U.S.A), whose numbers fell 3.28 percent to 2,844,952 members.
The only Protestant groups to report an increase in 2009 were the Assemblies of God, with an increase of 1.27 percent to 2,899,702 members, and the Tennessee-based Church of God, whose membership rose 1.76 percent to 1,072,169 members.
While many observers have attributed the membership decline to an increase in the secularization of the U.S., yearbook editor the Rev. Dr. Eileen Lindner advised otherwise.
"American society as a whole has not experienced the kind and rate of secularization so clearly demonstrated during the last quarter century in Western Europe," Lindner said.
"Indeed, American church membership trends have defied gravity particularly where the Pentecostal experience is included," she added.
Immigration has also been a force in the church's fight against secularism, according to Lindner, who said that most immigrants to the U.S. in the last 50 years have been Christian in their religious affiliation.
"In an era in which we have come to expect the inevitable advance of secularism in the U.S., the influx of robust Christian communities among new immigrants once again amends the topographical map," she said.
Furthermore, Lindner reported that while immigration has helped to strengthen the Christian faith in the U.S., it has also made major alterations to its character.
"With the racial, ethnic and cultural diversity of the immigrant communities more diverse and nuanced views of matters ranging from abortion to aid and trade policy as well as immigration policy may find voice as these churches enter into civic engagement in their new culture."
"As they do, a new fault line in Christian theology and practice may open within the American religious landscape."
Meanwhile, Yearbook reports on the Catholic Church showed a 1.49 percent increase in membership, with the group's numbers rising to 68,115,001 across the nation.
The Church of Jesus Christ of Latter-day Saints and the Jehova's Witnesses also saw increases in membership, with respective numbers at 1.71 percent to 5.9 million members, and 2 percent to 2 million members.
Eleven churches on the list, including the 5-million-member Church of God in Christ and National Baptist Convention of America, did not provide membership updates.
Total church membership reported in the 2010 Yearbook numbered 147,384,631 members, up 0.49 percent over 2009.
The top 25 churches reported in the 2010 Yearbook in order of size are:
1. The Catholic Church, 68,115,001 members, up 1.49 percent.
2. Southern Baptist Convention,16,228,438 members, down 0.24percent.
3. The United Methodist Church, 7,853,987 members, down 0.98 percent.
4. The Church of Jesus Christ of Latter-day Saints, 5,974,041 members, up 1.71 percent.
5. The Church of God in Christ, 5,499,875 members, no membership updates reported.
6. National Baptist Convention, U.S.A., Inc, 5,000,000 members, no membership updates reported.
7. Evangelical Lutheran Church in America, 4,633,887 members, down1.62 percent.
8. National Baptist Convention of America, Inc., 3,500,000 members, no membership updates reported.
9. Assemblies of God (ranked 10 last year), 2,899,702 members, up 1.27 percent.
10. Presbyterian Church (U.S.A.) 1(ranked 9 last year), 2,844,952 members, down 3.28 percent.
11. African Methodist Episcopal Church, 2,500,000 members, no membership updates reported.
11. National Missionary Baptist Convention of America, 2,500,000 members, no membership updates reported.
11. Progressive National Baptist Convention, Inc. 2,500,000 members, no membership updates reported.
14. The Lutheran Church-- Missouri Synod (LCMS), 2,337,349 members, down 1.92 percent.
15. The Episcopal Church, 2,057,292 members, down 2.81 percent.
16. Churches of Christ, 1,639,495 members, no membership updates reported.
17. Greek Orthodox Archdiocese of America, 1,500,000 members, no membership updates reported.
17. Pentecostal Assemblies of the World, Inc., 1,500,000 members, no membership updates reported.
19. The African Methodist Episcopal Zion Church, 1,400,000 members, members, no membership updates reported.
20. American Baptist Churches in the U.S.A., 1,331,127 members, down 2.00 percent.
21. Baptist Bible Fellowship International (ranked 22 last year), 1,200,000 members, no membership updates reported.
22. Jehovah's Witnesses (ranked 23 last year) 1,114,009members, up 2.00 percent.
23. United Church of Christ (ranked 22 last year), 1,111,691 members, down 2.93 percent.
24. Church of God (Cleveland, Tennessee), (ranked 25 last year), 1,072,169 members, up 1.76 percent.
25. Christian Churches and Churches of Christ (ranked 24 last year), 1,071,616 members, no membership updates reported.