PRINCETON, NJ -- The percentage of American adults who have no explicit religious identification averaged 17.8% in 2012, up from 14.6% in 2008 -- but only slightly higher than the 17.5% in 2011. The 2011 to 2012 uptick in religious "nones" is the smallest such year-to-year increase over the past five years of Gallup Daily tracking of religion in America.
To measure religious identity, Gallup asks respondents this question:
What is your religious preference -- are you Protestant, Roman Catholic, Mormon, Jewish, Muslim, another religion, or no religion? (If respondent names "another religion," ask:) Would that be a Christian religion or is it not a Christian religion?
Religious "nones" are those who respond "no religion" as well as those who say they don't know or refuse to answer.
The rise in the religious "nones" over time is one of the most significant trends in religious measurement in the United States. Virtually all Americans in Gallup surveys conducted in the 1950s and 1960s -- albeit in response to somewhat different types of questions -- had a religious identity. The percentage who did not report such an identity began to rise in the 1970s and has continued to increase in the years since.
Gallup Daily tracking, which started in 2008, encompasses about 350,000 interviews a year, and each of those interviews includes the question about religious identity. These unprecedented large samples produce annual estimates with very low margins of error, and thus the ability to look at year-to-year trends in granular detail.
Across the past five years, the biggest jumps in "nones" occurred between 2009 and 2010 and between 2010 and 2011 -- an increase of 1.1 percentage points each between the two years. In absolute terms, 15.3% of the population had no explicit religious identity in 2009, compared with 17.5% in 2011.
The rate of change between 2011 and 2012, however, slowed to a 0.3-point increase -- from 17.5% to 17.8%. These estimates are based on 353,492 interviews in 2011 and 353,571 interviews in 2012.
It is not clear what this slowed rate of change in no religious identity is attributable to, or if it signifies a lasting shift in the trend. There are a number of broad changes taking place in American society, including the inexorable aging of the huge baby boom generation born between 1946 and 1964, the ebbs and flows of the economy, changes in demographic patterns of immigration, migration among states, fertility, and marriage, and more abstract changes in the culture. All of these patterns are related to religion in some way.
The complete responses to the religious identity questions over the past years are presented on Page 2.
Asians, Young Adults, Those in the Pacific Region Most Likely to Be "Nones"
Religious "nones" differ from those who do have a religious identity in a number of ways, as detailed in the book God Is Alive and Well.
Those most likely to be "nones" include Asians, young people, those living in the Pacific and New England regions, political independents, and men. Those least likely to be "nones" include Republicans, older Americans, those living in the South, blacks, women, and Hispanics. These demographic and socioeconomic differences are consistent with other general measures of religiosity.
Americans' expression of an explicit religious identity in response to a survey interviewer's question is one of many measures of religiosity, although by no means a definitive measure of a person's religiousness or spirituality. The rise in "nones" partly reflects changes in the general pattern of expression of religion in American society today -- particularly including trends towards more "unbranded," casual, informal religion. And, although this "rise of the nones" has increased dramatically over recent decades, the rate of increase slowed last year, suggesting the possibility that there may be a leveling off in this measure in the years ahead.
Results are based on telephone interviews conducted as part of Gallup Daily tracking from 2008 through 2012, with random samples of 311,588 adults, aged 18 and older, living in all 50 U.S. states and the District of Columbia in 2008, 353,849 adults in 2009, 352,842 adults in 2010, 353,492 adults in 2011, and 353,571 adults in 2012.
For results based on the total sample of national adults for each year, one can say with 95% confidence that the maximum margin of sampling error is ±1 percentage point.
Interviews are conducted with respondents on landline telephones and cellular phones, with interviews conducted in Spanish for respondents who are primarily Spanish-speaking. Each sample includes a minimum quota of 400 cellphone respondents and 600 landline respondents per 1,000 national adults, with additional minimum quotas among landline respondents by region. Landline telephone numbers are chosen at random among listed telephone numbers. Cellphone numbers are selected using random-digit-dial methods. Landline respondents are chosen at random within each household on the basis of which member had the most recent birthday.
Samples are weighted by gender, age, race, Hispanic ethnicity, education, region, adults in the household, and phone status (cellphone only/landline only/both, cellphone mostly, and having an unlisted landline number). Demographic weighting targets are based on the March 2011 Current Population Survey figures for the aged 18 and older non-institutionalized population living in U.S. telephone households. All reported margins of sampling error include the computed design effects for weighting and sample design.
In addition to sampling error, question wording and practical difficulties in conducting surveys can introduce error or bias into the findings of public opinion polls.
For more details on Gallup's polling methodology, visit www.gallup.com.