Projections of Religiosity for Spain

Marcin Stonawski, International Institute for Applied Systems Analysis (IIASA) and Cracow University of Economics
Samir KC, International Institute for Applied Systems Analysis (IIASA)
Anne Goujon, Vienna Institute of Demography and International Institute for Applied Systems Analysis (IIASA)

We carry out multistate population projections by religion and religiosity in the period 2010-2050 for Spain. We investigate the impact of differential and converging fertility and various migration scenarios. We find that both fertility and migration increase the share of the highly religious, as more religious tend to have higher fertility, and immigrants tend to be more religious than the native population. There are also important mechanisms that are likely to lead to a less religious population. Those without religion belong to younger birth cohorts and population momentum implies that they will gradually replace older cohorts and represent a larger share of the population. Conversion and religious switching tends to benefit the secular population.