The 2010 Yearbook (representing 2008; collected in 2009) notes that recent declines in membership in the Catholic Church have reversed. “Dwarfing any single other church is the Catholic Church, reporting over 68 million adherents” (p, 11). CARA estimated the Catholic population in 2008 to be approximately 70.5 million (by comparison The Official Catholic Directory estimated this to be 65.2 million for the 50 states and Washington D.C. in 2008). The discrepancy between CARA’s estimate (survey-based) and those of the OCD and Yearbook is related to those who self-identify as Catholic but have no connection to any parish and thus do not get counted/estimated in officially reported totals.
Some of the other key findings from the 2010 Yearbook:
- Four of the 25 largest churches in the United States are Pentecostal and the Yearbook notes “a continuing increase in the number of adherents to Pentecostal groups” (p. 11).
- Of the largest 25 churches five grew by 1 percent or more between 2007 and 2008. These are: The Catholic Church (+1.49%), The Church of Jesus Christ of Latter-day Saints (+1.71%), Assemblies of God (+1.27%), Jehovah’s Witnesses (+2.00%), and Church of God in Cleveland, TN (+1.76%).
- The churches with the highest rate of membership decline include the Presbyterian Church U.S.A. (-3.28%), American Baptist Churches (-2.00%), The Lutheran Church-Missouri Synod (-1.92%), and the Evangelical Lutheran Church in America (-1.62%).
- Only three of the top ten largest churches are Mainline Protestant. In general, Mainline Protestant churches are experiencing an “acceleration of Church membership decline” (p.8).
