Maria Stanfors, Lund University
Marriage is a fundamental institution with implications for economic and social development. Changing age difference between spouses reflects social relations across time. It has decreased with modernization, presumably because marriage for sentimental, rather than instrumental, reasons became widespread, and further because of individualization and gender equality. We study long-term trends in spouses’ age difference, using longitudinal data on first marriages contracted in Sweden 1905-2009, and investigate implications of age differences in terms of divorce, 1905-2015. We use data from the Scanian Economic-Demographic Database (SEDD) that include individual-level longitudinal information from five rural parishes and one industrial port town in southern Sweden, covering 61,868 marriages contracted in 1905–2009. We use logistic regression models to estimate the risk of divorce dependent on age heterogamy and other factors. Results confirm increasing age homogamy in terms of average age difference between partners over the 20th century. Age homogamy is associated with longer marriages. Age heterogamy is positively associated with divorce risks across marriage cohorts from the 1960s onwards. As expected, hypogamy (i.e., wife being older than husband by less than a year) is associated with the highest divorce risk. After 1970, age heterogamy is generally associated with higher divorce risks compared to homogamy. The results suggest that hypogamy is still an important determinant of divorce, perhaps because it becomes more norm-breaking when age homogamy becomes standard and more reflective of the population’s orientation towards similarity between partners. This indicates that marriage is a gendered institution even in a relatively gender-equal context, like contemporary Sweden. The results provide new evidence on union formation patterns and the implications of assortative mating for union stability in a long-run perspective.