In two earlier posts (here and here), I examined global, regional and country-level trends in religious belief and practice, and the prevalence of atheism. The analysis was based on data from the  World Values Survey (WVS) and the European Values Study (EVS), covering the period 1981 to 2020. Earlier this year, I discovered that the World Values Survey dataset has been updated. Some data collected using a mobile phone app in the most recent US survey was incorrectly coded and this mainly affected the religiosity categories.  Comparison of the US prevalences for religiosity show that the coding errors resulted in an overestimate of the atheist and non-religious categories as shown in the following table:

Comparison of religiosity prevalence estimates
 for USA in year 2020

I have now updated the previous analyses using the 2021 release of the combined data for the WVS and EVS in the Integrated Values Surveys (IVS) 1981-2021 [1-3]. In carrying out these updates, I also addressed some definitional issues which have resulted in mostly slight changes to estimates for other countries. The details of the updated analysis are described elsewhere.

The four religiosity categories have now defined as:

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 the top 5 points of a 10 points 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 the top 6 points.

Non-religious: A non-religious person who believes in God but rates the importance of God as any of three points at the not important end of a 10-point scale.

Atheist: A “confirmed atheist” and/or does not believe in God

* I have assigned all people who do not believe in God to the atheist category. This will include some religious people who practice non-theist religions such as Buddhism. This differs from the previous definition.

** 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.

For the 110 countries with IVS survey data for years 2000 or later, the prevalences of the four religiosity categories across survey waves were projected forward to 2020. The following plot shows the estimated prevalence of all religiosity categories in 2020 for countries ranked in descending level of irreligion (atheist + non-religious).

There are 18 countries where more than half the population are estimated to be atheist in 2020. These include China,  South Korea, Japan, Vietnam and Thailand, all Asian countries with Buddhist and non-theist religious traditions. They also include all the Scandinavian countries and European countries such as France, the Netherlands and the United Kingdom, as well as Australia and New Zealand.     At the other end are six countries where the prevalence of irreligion is estimated at less than 1% of the population.

Full time series of religiosity trends from 1980 to 2020 were imputed for the 110 countries using the same methods as before. The updated trends are generally similar to those previously posted (see here), except for the USA. The revised data for the USA shows that the prevalence of atheism has increased rapidly in the 21^st century from around 6% to almost 23% in 2020 and the prevalence of non-religious has also increased from 2.2% to 6.9%.

The prevalence of irreligion (atheists and non-religious) has increased in the USA by an estimated 21.5 percentage points over the last two decades, the fourth largest increase of any country included in this analysis. The largest increase occurred in neighboring Canada with a 36.7% increase since year 2000.  Apart from two Asian countries (South Korea and Singapore) and Hong Kong, all the other countries in the top 20 for increase in irreligion since 2000 are high income countries. And apart from Chile, Australia and New Zealand, all of these are in Europe and North America.

I have also computed revised trends for the 11 culture zones used in previous posts (see here). The following plots show estimated religiosity trends for the world as a whole and for these 11 culture zones:

These plots illustrate the extreme diversity of religiosity trends across regions. Western countries (Reformed West, Old West, North America) are characterised by rapidly rising prevalence of atheism and corresponding decline in practicing religious. The former Eastern bloc countries (Returned West, Orthodox East) are characterised by a large drop in atheism prevalence and corresponding rise in religious categories following the collapse of the Soviet Union around 1991. More recently, atheism is rising and practicing religious falling in the Returned West, following a similar path to that taken by Western Europe.

The Orthodox East has had continuing decline in atheism and the non-practicing religious have become the dominant group at around 55% of the population, far more than the practicing religious. 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) is 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.

Latin America, the Islamic East and Sub-Saharan Africa are the “religious” culture zones characterised by very high prevalences of practicing and non-practicing religious people and very low prevalences of non-religious and atheists. The Indic East also has very low prevalences of the irreligious, but in contrast to the other “religious” zones, has had a shift from practicing to non-practicing religious. This may very well be largely reflecting the increasing levels of Hindu nationalism in India. Iran and other Islamic countries generally report very low levels of atheism, 2.4% on average, and I suspect this is lower than reality because of the quite severe social and legal consequences in many Islamic countries. As discussed in a previous post, there is some evidence that irreligious respondents are fearful of being identified if they respond honestly to a telephone interview.

At global level, the prevalence of practicing religious has barely changed over the last 40 years, as has the prevalence of atheism, but there has been a shift from non-religious to atheist and to non-practicing religious, the latter reflecting mainly the change in former Soviet bloc countries. The relatively small changes in prevalence of religiosity at global level over the last 40 years conceal quite substantial changes in developed countries and in former Soviet countries, in opposing directions. The following table summarizes global changes in the prevalence of religiosity categories over the 40-year period 1980 to 2020.

The overall global prevalence of irreligion (atheist plus nonreligious) has declined somewhat, but a substantially higher proportion of the irreligious identify as atheist in 2020 compared to 1980. Is irreligion likely to increase in the future? If the economies of developing countries continue to grow, with decreasing levels of poverty, and education levels continue to improve, it is likely that religiosity in these countries will decline in the longer term. But if the pandemic and global heating crises derail the historical development trends, then population growth due to the higher fertility levels of Islamic and African countries will ensure that the overall religiosity of the world will increase in the future.  In an era of joint global environmental and pandemic crises, with rising populism and rejection of science and global institutions, it is entirely possible that the developing countries will not pass through the equivalent of the Western Reformation which resulted in freedom of thought and religion and decreasing levels of premodern religious values.

References

1. EVS (2021): EVS Trend File 1981-2017. GESIS Data Archive, Cologne. ZA7503 Data file Version 2.0.0, https://doi.org/10.4232/1.13736
2. EVS/WVS (2021). European Values Study and World Values Survey: Joint EVS/WVS 2017-2021 Dataset (Joint EVS/WVS). JD Systems Institute & WVSA. Dataset Version 1.1.0, doi:10.14281/18241.14.
3. Haerpfer, C., Inglehart, R., Moreno, A., Welzel, C., Kizilova, K., Diez-Medrano J., M. Lagos, P. Norris, E. Ponarin & B. Puranen et al. (eds.). 2021. World Values Survey Time-Series (1981-2020) Cross-National Data-Set. Madrid, Spain  &  Vienna,  Austria:  JD  Systems  Institute  &  WVSA Secretariat. Data File Version 2.0.0, doi:10.14281/18241.15.