The World Values Survey (WVS) and the European Values Study (EVS) include questions on religious affiliation, religious beliefs and practices, as well as on the influence of religion on attitudes to government, politicians and science [1-4]. These questions played a major role in the analysis of traditional values versus secular-rational values across countries and time (see my previous posts here and here).
This post takes a closer look at what the WVS/EVS data for 110 countries tells us about levels of religiosity and atheism. Quite often, estimates of the prevalence of atheism (the lack of belief in God or gods) have been based on either self-report of no religious affiliation, or self-identification as “non-religious” or “confirmed atheist” (both types of questions are included in the WVS/EVS). The WVS/EVS also includes a direct question on belief in God (Yes/No) and questions on frequency and type of religious practices. I’ve used these to estimate the prevalence of atheism for all countries of the world in 2020 using multiple questions to develop a more rigorous classification of religiosity and atheism. This is a work in progress and these are provisional results which may be further revised.
The atheist and other categories of religiosity are constructed from the following survey questions:
Respondents are classified as “practicing” if they attend religious services or pray to God outside of religious services at least once a month. Otherwise, they are classified as non-practicing. Excluding people who state an affiliation with a non-theist religion (a very small proportion of respondents in most countries outside parts of Asia), the categories are defined as follows:
Atheist: A “confirmed atheist” and/or does not believe in God
Non-religious: A non-religious person who believes in God, but rates the importance of God as 8-10 at the not important end of a 10-point scale.
Non-practicing religious person: A religious person who believes in God and is non-practicing OR a non-religious person who believes in God, is non-practicing, and rates the importance of God in range 1-7.
Practicing religious person: A religious person who believes in God and is practicing, OR a non-religious person who believes in God, is practicing, and rates the importance of God in range 1-7.
Modified versions of these definitions are used for persons with non-theist religion and in the predominantly Buddhist countries (see Endnote a). A larger scale map of variations in atheism prevalence for European countries is shown in Endnote b.
For the 104 countries with survey data for years 2005 or later (Endnote c), prevalences of the four religiosity categories across survey waves were projected forward to 2020 (Endnote d). Of the 104 countries, 76 have data for year 2017 or later, and another 17 have latest year of data on or after 2010. For the maps, I have also imputed religiosity for 56 countries not included in the WVS/EVS (Endnote e).
The following figure shows examples of these trends for four countries. Data for the USA suggest that the prevalence of atheism has increased rapidly in the 21st century from around 6% to 23% and the prevalence of non-religious people has also increased from less than 2% to 12%. The prevalence of irreligion (atheists and non-religious) has increased by an estimated 30 percentage points over the last two decades, the largest increase of any country included in this analysis. Closely behind is South Korea, followed by Iceland, the Netherlands, Spain, Finland, Norway, the UK and Australia (15 percentage point increase). The overall prevalence of irreligion is higher in these other countries, but the USA is catching up. The plot for Russia illustrates the pattern of decline in atheism and the increase in practicing and non-practicing religious people that is typical of former Soviet-bloc communist countries. China has the largest prevalence of atheism in the world at an estimated 78% but as the plot shows there has been a substantial shift from the non-religious category to the atheist category and its difficult to interpret this given the lack of fit of the WVS questions for the non-theist religions and practices that are most common in China.
The following plot shows the estimated prevalence of all religiosity categories in 2020 for countries ranked in descending level of irreligion.
The next figure shows the estimated average prevalence of atheism and religiosity for Welzel’s culture zones defined in my previous posts. As Australia and New Zealand have religiosity distributions very similar to those of northern Europe, they have been included with the Reformed West and the New West relabeled as North America.
The Orthodox East includes former Soviet-bloc countries that are predominantly Orthodox Christian or Muslim. These countries are characterized by a much higher prevalence of non-practicing religious people than other culture zones. A 2018 Pew Research Center Report  examined this more closely and found that for most people in the former Eastern bloc, being Christian (whether Catholic or Orthodox) s an important component of their national identity, with many people embracing religion in the post-Communist period as an element of national belonging, even though they are not highly religious.
The following figure plots the reported religious affiliation of religious people by culture zone, using 2020 estimated prevalence of religious people together with the distribution of religious affiliation reported in the most recent wave survey for people classified as religious.
It is difficult to assess time trends for religiosity as its very difficult to distinguish variations in measurement error across surveys from real trends for some countries. In a following post, I will examine time trends and the question of whether irreligion is increasing or decreasing for the world and for various culture zones.
a. Defining religiosity and atheism for non-theist religions
The WVS/EVS questions, and those of other similar survey programs, are biased towards monotheistic religions and do not adequately take the non-theistic religions into account (these include Buddhism, Confucianism, Taoism, Jainism). Thus “confirmed atheist” is a separate category to “religious person” although around half of practicing Buddhists in the surveys said they do not believe in God. For respondents who report affiliation with a non-theistic religion, the religiosity categories are modified as described in footnote b. A more accurate label for the “Atheist” category that takes non-theist religious people into account would be “Non-religious atheist”.
Atheist: A confirmed atheist”, practicing once a year or less and considers religion to be “not at all important”, OR a religious or non-religious person who does not believe in God, is not practicing and considers religion to be “not at all important”
Non-religious: A not religious person, who believes in God but considers religion not at all important, and is not practicing.
Non-practicing religious person: A religious person who is non-practicing OR a non-religious person who practices less than once a month and more than once a year, and rates the importance of religion greater than “Not at all”
Practicing religious person: A religious person who is practicing OR a not religious person or confirmed atheist who is practicing and considers religion to be more than “Not at all important”
This is not entirely adequate to deal with the non-theist issue, as adherents of non-theist and folk religions may often interpret the question on religious affiliation as referring to the major established religions, and respond “None”. This is only an important issue for Sinic countries and other countries in Asia where Buddhism is a major religion. The religiosity results for these countries should be treated with caution, they vary substantially across the countries and across waves and time, and its likely that there are considerable measurement issues resulting from variable interpretation of questions framed largely for theist religious beliefs.
b. The prevalence of atheism in Eurasian countries, 2020
c. Countries without data for years 2005 or later
Of the 110 countries for which data is included in the WVS or EVS, six have been excluded as they have no data for any years from 2005 onwards. These are the Dominican Republic, El Salvador, Saudi Arabia, Tanzania, Uganda and Venezuela.
d. Projection of religiosity prevalences to year 2020
Trends in prevalence of atheism and other religiosity categories were projected forward to year 2000 using logistic regression of country-specific prevalences against time with weights decreasing at 5% per year for years prior to 2020 (in order to give higher priority to recent trend). Projected trends are sensitive to variations across waves due to survey and sampling variations and outlier trends were adjusted towards the 75th percentile trend for each culture zone.
e. Imputation of religiosity for countries not included in the WVS/EVS.
Religiosity categories were imputed for 12 countries using data from Win/Gallup surveys for years 2012, 2015 and 2017 [6-8] which includes a question “Are you a religious person?” with the same response categories as the WVS/EVS question. These countries were Afghanistan, Cameroon, the Democratic Republic of the Congo, Cuba, Fiji, Kenya, Mongolia, Panama, Papua New Guinea, North Korea and South Sudan. Prevalences for religiosity category for Israel were imputed from a Pew Research Center survey which also included similar questions on religiosity .
For the remaining 43 countries with population greater than 1 million in 2020 (28 of these in Africa), religiosity was imputed using culture-zone-specific regressions of the WVS/EVS religiosity prevalences against Pew Research Center country-specific estimates for the year 2020 of religious affiliation distributions for 8 religious categories, including “other” and “none” .
- Inglehart, R., C. Haerpfer, A. Moreno, C. Welzel, K. Kizilova, J. Diez-Medrano, M. Lagos, P. Norris, E. Ponarin & B. Puranen et al. (eds.). 2014. World Values Survey: All Rounds – Country-Pooled Datafile Version: https://www.worldvaluessurvey.org/WVSDocumentationWVL.jsp. Madrid: JD Systems Institute.
- Haerpfer, C., Inglehart, R., Moreno,A., Welzel,C., Kizilova,K., Diez-MedranoJ., M. Lagos, P. Norris, E. Ponarin & B. Puranen et al. (eds.). 2020. World Values Survey: Round Seven–Country-Pooled Datafile. Madrid, Spain & Vienna, Austria: JD Systems Institute& WVSA Secretariat[Version: http://www.worldvaluessurvey.org/WVSDocumentationWV7.jsp].
- Gedeshi, Ilir, Zulehner, Paul M., Rotman, David, Titarenko, Larissa, Billiet, Jaak, Dobbelaere, Karel, Kerkhofs, Jan. (2020). European Values Study Longitudinal Data File 1981-2008 (EVS 1981-2008). GESIS Datenarchiv, Köln. ZA4804 Datenfile Version 3.1.0, https://doi.org/10.4232/1.13486.
- EVS (2020): European Values Study 2017: Integrated Dataset (EVS 2017). GESIS Data Archive, Cologne. ZA7500 Data file Version 3.0.0,doi:10.4232/1.13511
- Pew Research Center, Oct 29, 2018. Eastern and Western Europeans Differ on Importance of Religion, Views of Minorities, and Key Social Issues. https://www.pewforum.org/2018/10/29/eastern-and-western-europeans-differ-on-importance-of-religion-views-of-minorities-and-key-social-issues/
- WIN Gallup International. Global Index of Religiosity And Atheism – 2012. WIN-Gallup International. 27 July 2012.
- WIN Gallup International. Losing Our Religion: Two Thirds of People Still Claim to Be Religious. WIN/Gallup International. 13 April 2015.
- WIN Gallup International. Religion Prevails in the World. WIN/Gallup International. 10 April 2017.
- Pew Research Center, March 8 2016. Israel’s Religiously Divided Society. https://www.pewforum.org/2016/03/08/israels-religiously-divided-society/
- Pew Research Center, April 2 2015. Religious Composition by Country, 2010-2050. https://www.pewforum.org/2015/04/02/religious-projection-table/2020/number/all/