Counting the Population or Describing Society? A Comparison of English and Welsh and French Censuses

Data collected at household level in censuses are used for a wide range of purposes including practical planning and academic analysis of changing social conditions. Comparability is a core demographic value, and to understand the limits of the comparability of census data across time and space, it is important to recognise if, how and why, concepts and definitions change between censuses. This paper examines definitions of the household in censuses in England and Wales (E&W) and France from 1960 to 2012 in order to investigate how census definitions have changed and to examine the drivers of such changes. Two research methods were used: (1) longitudinal analyses of census documentation since the 1960s and (2) in-depth interviews with key informants oriented around respondents' roles in the collection and/or use of household data from censuses and surveys. We identify two contrasting national approaches to the data collection exercise that is called a census, which reflect political and institutional differences. These differences call into question the comparability of some aspects of census data across national boundaries, despite increased harmonisation of approaches to data collection. By comparing the evolution of the definitions of the "household" in censuses, we develop insight into the diversity of the priorities of census commissioners and designers, and consider the broader implications of this for producing comparable data.