Moving Away from Religion: Age, Cohort, or Period Effect? Evidence from a Longitudinal Survey in Switzerland

Since Voas and Crockett (2005), a consensus has emerged in the sociology of religions on the fact that secularization is largely due to a cohort effect. That is, each birth cohort is less religious than the previous one. We use data from the Swiss Household Panel (SHP), a multi-thematic survey based on a random sample representative of the general population since 1999, to understand what is the cohort effect in Switzerland on three indicators of religiosity: religious affiliation, frequency of religious service attendance, and personal prayer, taking into account the socio-demographic characteristics of individuals, which could interfere with cohort, period, or age effects. A first general observation can be drawn from the SHP: for the three religious indicators, a cohort effect is a key factor in explaining the decline of religiosity. Each birth cohort is less religious on all three indicators, that is, younger individuals are less affiliated, practice less often, and pray less than the older cohort. More subtly, we also observe an effect of age or life cycle, especially on the practice, and a period effect on the religious disaffiliation of individuals. Each birth cohort shows a more religious profile of individuals at the start of the cohort than at the end. There is, therefore, an initial movement of distancing from religion by birth cohorts, but this is further accentuated by a period effect for disaffiliation and sometimes accelerated and, at other times, slightly contained by a life-cycle effect.