The aim of the population census is to count the homes and the population living in France and to determine their main characteristics: gender, age, activity, professions, characteristics of the households, size and type of housing, modes of transport, daily travel. The census, started in 1801, was performed every 5 years up to 1936. From 1946 to 1999, the periods between one census and the next varied from 6 to 9 years. The information collected is of interest to the local authorities, the State departments but also enterprises, sociologists, town planners, etc.
Such information helps to define :
- on the national level, the social policies and infrastructures to be implemented ;
- on the local level, the urban policies for transport, housing, cultural and sports facilities, school infrastructures and the installation of facilities for young people and senior citizens. For private stakeholders, the census is used for projects for the location of enterprises, shops and services.
The law of 27 February 2002 on local democracy brought about an in-depth change in the census methods. Since January 2004, the traditional count has been replaced by annual census surveys. Municipalities with less than 10,000 inhabitants are still covered by an exhaustive census as in the past but once every 5 years instead of every 8 or 9 years. The municipalities of 10,000 inhabitants and over are now covered by an annual survey but on a sample of 8% of the population, scattered over their territory. After 5 years, the entire territory of these municipalities has been covered and the results of the census are calculated on the basis of a sample of 40% of the population thus constituted.
As from the end of 2008, after the first five census surveys, INSEE will publish for the first time the legal population of each municipality and then, as from 2009, the complete statistical results on the inhabitants and their housing. However, before 2008, INSEE will publish provisional results taken from the annual census surveys.
Until the publication at the end of 2008 of the first decree authenticating the official populations calculated by the new census, the populations authenticated in 1999 (or further to complementary censuses) remained in force.