A global perspective on household size and composition, 1970-2020

Households are core units of social organization and reproduction, yet, compared to other areas of demographic research, we have limited understanding of their basic characteristics across countries. Using data from 793 time points and 156 countries in the new CORESIDENCE database, this article provides a comprehensive analysis of global household size and composition trends. The findings reveal that despite significant international variations in household size, ranging from 1.8 in Denmark to 8.4 in Senegal, there is a widespread decline in household size. On average, households have decreased by approximately 0.5 persons per decade. Children contribute to over three-quarters of the observed variability and decline in household size in recent decades. In contrast, the number of other relatives in households has remained relatively stable or has only moderately decreased. While households are becoming more similar in size, their composition is not converging globally to the same extent. These dynamics have macro and micro-level implications for families, societies, and the economy. Further investigation is required to understand the underlying factors driving these transformations and their consequences.