The nation's largest Protestant denomination reported a decline in membership for the second year in a row, according to the National Council of Churches' 2010 yearbook of churches.
The Catholic Church, meanwhile, rebounded from last year's reported membership loss with a 1.49 percent growth, joining church bodies including the Assemblies of God and the Church of God in Christ as the few large U.S. denominations with reported growth.
Also reporting growth in NCC's 78th annual Yearbook of American & Canadian Churches were the Church of Jesus Christ of Latter-day Saints and Jehovah's Witnesses – though a significant number of the two organizations' core beliefs are considered by conservative Bible scholars as contradictory to historic orthodox Christianity.
Notably, the NCC reported in its announcement of the 2010 yearbook's release Friday that eleven of the 25 largest churches did not report updated figures.
Furthermore, membership figures reported in the 2010 yearbook were collected by the churches in 2008 and reported to the yearbook's staff in 2009.
Despite the delay and lack in new stats, the yearbook continues to provide a unique look at the nearly 230 national church bodies as well as information on nearly 240 U.S. local and regional ecumenical bodies.
In her remarks on this year's stats – which, again, are actually from 2008 due to the reporting delay – the Rev. Dr. Eileen W. Lindner, editor of the annual yearbook since 1998, acknowledged the continued loss of membership in the largest mainline denominations.
This year, church bodies reporting the highest membership losses were the Presbyterian Church (USA), down 3.28 percent to 2,941,412; American Baptist Churches in the USA, down 2 percent to 1,358,351; and the Evangelical Lutheran Church in America, down 1.92 percent to 4,709,956 members.
Though she noted that many observers have attributed accelerated membership decline of some churches to "an increasing secularization of American postmodern society, and its disproportionate impact on liberal religious groups," Lindner advised caution in assessing the causes of decline.
She also said statistics in the yearbook actually reflect "continued high overall church participation, and account for the religious affiliation of over 163 million Americans."
"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. Indeed, American church membership trends have defied gravity particularly where the Pentecostal experience is included," she added.
Lindner also noted that the largest plurality of immigrants to the United States 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 reported.
So while a number of denominations have reported losses, overall, the Church in the America is growing.
Total church membership reported in the 2010 Yearbook was 147,384,631 members, up 0.49 percent over 2009.
That figure has been rising every year since 2006, when the overall membership total dropped for a second straight year following a record high 161 million.
As the yearbook only records figures from national church bodies, the total membership value doesn't take into consideration the multitude of non-denominational churches scattered across America.
The following is list of the largest 25 church bodies in order of size, according to NCC's 2010 yearbook:
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.