Age and cohort change

Age and cohort change (ACC) researchers within the World Population Program (POP), continued working, in collaboration with Pew Research Center, on population projections of religious denominations around the world.

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Two scientific papers [1] [2] based on research into population projections of religious denominations were accepted by the peer-reviewed international journal, Yearbook of International Religious Demography, and will be published in 2015.

ACC started a new project with the Pew Research Center entitled “Religion-Education-Demography” on cohort changes in education among religious denominations in the world. The main objective in 2014 was to build the global database of data on education and religion needed for the project and evaluate and test methods that will be used for analysis planned for 2015.

POP scientists investigated the demographics of religious communities in Spain [1]. Projections of the expected change of religious intensity in population were prepared based on these findings. The results of this exercise suggest that in the longer term (2050), there may be a decline in the share of Christians of high religiosity and moderate development of Christians of low religiosity in Spain. The population with no religion will grow in the future and the Muslim population will increase substantially, unless there is an end to migration and fertility differentials between Muslims and other religious groups converge.

In 2014 Vegard Skirbekk and Marcin Stonawski, together with international collaborators, carried out research on the association between Buddhism and fertility among Asian nations [2]. The results suggest that being affiliated to Buddhism tends to be negatively or not associated with childbearing outcomes, when education, region of residence, age, and marital status are controlled for. Although the results vary between the highly diverse contextual and institutional settings investigated, there is evidence that Buddhist affiliation or devotion is not related to elevated fertility across the different cultural settings, but rather the opposite – that Buddhism is related negatively or insignificantly to fertility. These findings stand in contrast to studies of Abrahamic religions, which tend to show a positive link between religiosity and fertility. 


[1] Stonawski M, Skirbekk V, Kaufmann E, Goujon A (2015) The end of secularisation through demography? Projections of Spanish religiosity. Journal of Contemporary Religion, 30(1):1-21 (January 2015).

[2] Skirbekk V, Stonawski M, Fukuda S, Spoorenberg T, Hackett C, Muttarak R (2015) Is Buddhism the low fertility religion of Asia? Demorgaphic Research, 32(1):1-28 (January 2015).


Pew Research Center, Washington, DC, USA.

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Last edited: 21 April 2015

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Age and Cohort Change

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