A census is a survey conducted on the full set of observation objects belonging to a given population or universe.
Population and housing census
A population and housing census provides an opportunity to obtain a comprehensive and accurate picture of the population and the housing stock. It is a considerable undertaking, which provides a unique source of data that is invaluable for policy formation, as comparable data are collected for small areas (municipalities) that may be aggregated up through regions, to national and international aggregates. It may also be used to collect information on the main characteristics of individuals, families, households and the dwellings in which they live, in other words a range of geographic, demographic, social and economic information.
The results of a population and housing census are unique insofar as they provide detailed information down to the level of individual municipalities, while also providing a means to produce cross-tabulations of different variables. The essential features that distinguish a population and housing census from other data collections are:
- individual enumeration — in other words, the characteristics of each individual person and dwelling are separately recorded, allowing the cross-classification of various characteristics;
- simultaneity — the information obtained on individuals and dwellings refers to a specific and unique reference period;
- universality — the census provides data that covers all persons, households and dwellings in precisely defined territorial areas;
- small-area data — the census allows data to be produced for the smallest geographic areas of a country and for small subpopulations, subject to the protection of confidentiality.
Given its scope and magnitude, a population and housing census is generally conducted once every 10 years in Europe, although a few of the EU Member States have decided to conduct an annual census and others have censuses every five years. The latest census for all of the Member States and EFTA countries was conducted in 2011 and it entailed comprehensive administrative preparations by a wide range of public agencies including local, regional and national authorities, as well as national and international statistical agencies.
For the 2011 exercise, European legislation defined (for the first time) a detailed set of harmonised data to be collected in each EU Member State, based on international guidelines and recommendations prepared by the United Nations, Eurostat and the individual offices of each national statistical authority. As such, census data reflect extensive planning and close cooperation and consultation between Eurostat and the national statistical authorities, designed to facilitate the widest possible use of the population and housing census as a key resource for European social statistics. Each EU Member State was free to develop data collection and processing methods that they considered to be best suited to their own administrative practices and traditions.
- Source: Glossary of Statistical Terms, OECD, 2005