Religious Congregations and Membership Study 2010

Posted: 5/1/2012

Catholic Data in U.S. Religious Affiliation Study Released

Map of Catholic Church AdherentsThe most complete data available on U.S. religious affiliation was released on May 1, 2012, at a press conference during the annual meeting of the Associated Church Press in Chicago. The 2010 U.S. Religion Census: Religious Congregations & Membership Study, a county-by-county enumeration of religious bodies in the United States, is the latest in a series of every-10-year studies conducted at the same time as the U.S. census.

The Glenmary Research Center (GRC), founded in 1966, was a key stakeholder in the development of studies released in 1971, 1980, 1990 and 2000. The GRC is responsible for and funds the collection of the data for Catholic (Latin and Eastern Rite) parishes throughout the United States and is disseminating the Catholic data included in the study. The GRC is also distributing the "Major Religious Families of the United States" wall map. The Association of Statisticians of American Religious Bodies (ASARB) serves as the publisher of the 2010 study.

Geographic Trends

The Catholic data shows the populations in the urban areas of the Northeast and Midwest are declining. While the Northeast, a traditionally Catholic region, continues to have the highest Catholic population (18.3 million), the 2010 study shows a shift in this population to the urban areas of the West and South while the number of Catholic churches by region has remained more stable.

As a result, the number of Catholics per church has grown in the South and, particularly, the West. In 1971, there were less than 2,000 Catholics per church in the West. In 2010, there were nearly 4,200, with nearly 7,800 per church in California. The rural South, where the majority of Glenmary missions are located, continues to be the least Catholic region in the country.

"The out-migration from the Northeast and Midwest has been a trend over the past several decades," says Cliff Grammich, who compiled the Catholic data. "Some of the northeastern dioceses show a huge drop in Catholic population in this study because the number of deaths have been exceeding the number of infant baptisms. In some dioceses, there are only two infant baptisms for every three Catholic deaths."

Catholic Population Declined?

The data collected for the study also show the total number of Catholic adherents—the number of baptized Catholic individuals recognized by each parish and mission in the United States—at 58.9 million, three times that of the second-largest religious body, the Southern Baptist Convention.

Grammich noted that the total number of Catholics in the United States reported in the 2010 study indicates, on the surface, a decrease of approximately 5 percent from the 2000 total of 62 million. But, because the methodology used to collect the data changed for the 2010 study, he says it's difficult to draw absolute conclusions when comparing the Catholic statistics in the two studies. (Read more about the definitions used in the study and the accuracy of the statistics.)

For the 2010 study, U.S. parishes and missions were asked to provide sacramental and vital statistics for the past year that included the number of registered households and individuals, infant baptisms, funerals and those attending Mass. From those statistics, the number of active, recognized Catholics was aggregated. In the past, the statistics were provided by dioceses.

The decision to change to a more congregational-based methodology was made, Grammich says, to obtain "a more realistic" number of active Catholics in the United States and to provide a "definition comparable to those of other religious bodies in the study. As a result, the 2010 study represents a more accurate picture of U.S. Catholics who are recognized by and affiliated with specific church communities.

"Some national surveys indicate that about 25 percent, or more than 75 million persons, in the United States identify themselves as Catholic. Yet these same surveys show only about two-thirds of those claiming to be Catholic, or about 50 million, say they attend religious service more than once yearly." Grammich said.

More Details on the Overall Study

The 2010 U.S. Religion Census: Religious Congregations & Membership Study reports that 150 million Americans (48.8 percent of the population) were associated with the 236 reporting religious bodies. The 2000 Religious Congregations and Membership Study included data on only 149 church/congregational groupings.

The 2010 survey also includes the number of churches/congregations, full members and adherents for each group in each county in all 50 states. Data are also presented by state, region and religious group.

In addition to Christian groups, the survey includes Jewish data by congregation for four traditions: Conservative, Orthodox, Reconstructionist, and Reform; Muslim data for more than 2,100 congregations; Buddhist adherent and congregation data for 215 different bodies; Hindu adherent and congregation data for 127 different bodies; and continued coverage of the Bahá'í, Jain, Sikh, and Zoroastrian traditions.

For more information regarding the Catholic data collected for the 2010 study or related materials, contact the Glenmary Research Center.