Census 2021 round (cens

1.1. Contact organisation

Insee: National Institute of Statistics and Economic Studies

1.2. Contact organisation unit

Direction des Statistiques Démographiques et Sociales

Département de la Démographie

1.3. Contact name

Confidential because of GDPR

1.4. Contact person function

Confidential because of GDPR

1.5. Contact mail address

Muriel Barlet

Insee

Direction des Statistiques Démographiques et Sociales

Département de la Démographie

88 avenue Verdier

CS 70058

92541 MONTROUGE CEDEX

1.6. Contact email address

Confidential because of GDPR

1.7. Contact phone number

Confidential because of GDPR

1.8. Contact fax number

Confidential because of GDPR

2.1. Metadata last certified

20 February 2025

2.2. Metadata last posted

20 February 2025

2.3. Metadata last update

20 February 2025

3.1. Data description

The data present the results of the 2021 EU census on population and housing, following Regulation (EC) 763/2008; Regulation (EU) 2017/543; Regulation (EU) 2017/712 and Regulation (EU) 2017/881.

The French census includes inhabitants from metropolitan France and inhabitants of French overseas departments (Guadeloupe, including Saint-Martin, Martinique, La Réunion, Guyane ; data for Mayotte is not available for the 2021 Census). The overseas territory of Saint-Martin is included in the NUTS3 region of Guadeloupe.

Population and housing censuses provide a precise and geographically detailed count of the population in a country. They offer information about a wide range of population characteristics at a very detailed level of crossclassification.

The 2021 census specifications include geographic, demographic, economic and educational characteristics of persons; international and internal migration characteristics; and household, family and housing characteristics. In addition, some topics of the 2021 population and housing census are disseminated on a 1 km² grid (number of persons), for metropolitan France.

Two data sets are delivered:

119 data hypercubes, at different geographical levels (the whole nation, excluding Mayotte, NUTS 1 for the French regions, NUTS 2 for the old French regions, NUTS 3 for the French departements and LAU 2 for the municipality level), relating to population, households, families, living quarters and conventionnal dwellings;
1 km² grid data (number of individuals), with several topics :
- total population
- sex (male/female)
- age (under 15 years, between 15 and 64 years, 65 years and over)
- country of birth (in th reporting country, in other EU Member State, elsewhere)
- place of usual residence one year prior to the census (usual residence unchanged, move within the reporting couuntry, move from outside the reporting country)
The current activity status, according to the ILO, should be provided as far as possible: it is not provided by France.

3.1.1. Impact of the COVID-19 pandemic on census methodology

Data collection in 2021 did not take place and was postponed to 2022 (except for persons living in houseboats).

The calculation methods have been adapted for the population living in conventionnal dwellings (see below).
For persons living in an institutionnal household, or in a « mobile housing unit », and for homeless persons, the last population collected was kept for a further year.

Adaptation of the calculation method of populaiton living in conventional dwellungs due to the report of the 2021 Census survey:

In municipalities with fewer than 10,000 inhabitants, a traditionnal census is conducted every 5 years. INSEE determines the legal populations for the median year of the 5-year cycle either by counting the number of forms filled in municipalities surveyed that year, or by extrapolation or interpolation of the results obtained by the most recent census survey for the other municipalities, surveyed before or after the reference year. In the case of extrapolation, these calculations consist of extending observed trends based on the number of dwellings provided by the tax data, and in the case of interpolation, establishing intermediate figures between two years for which the populations are known.

The adapted method consists in applying for a further year the extrapolation method normally used for the two reference years following the data collection.
To calculate the 2021 population:

- for municipalities surveyed in 2019 and 2020, the 2021 population is extrapolated (no change in the calculation method);
- municipalities that should have been surveyed in 2021 and 2022 were surveyed in 2022 and 2023: the 2021 population has been interpolated (minor changes in the calculation method);
- municipalities that should have been surveyed in 2023 were surveyed in 2024. These 2024 data were not yet available to calculate the 2021 population, so we have extrapolated data from the previous survey, in 2018 (third extrapolation instead of the usual two).
In municipalities of 10,000 inhabitants or more, census surveys are carried out every year by sampling. Each municipality is divided into five groups and each group is surveyed during one year of the 5-year cycle. The principle of the calculation consists of adding up the observations of the five years surrounding the reference date, then deducting the entire municipality by referring to the number of dwellings at the reference date, as known by the localized building register (Ril). To obtain the number of persons by dwelling:
- administrative data (building register – RIL) give the number of dwellings in 2021;
- data from the 2019, 2020, 2022 and 2023 surveys were used (no change) ;
- for the group which should have been surveyed in 2021, data from the previous survey (in 2016) were used and updated, based on housing and population trends.

For further information: Adaptation of the calculation method of populaiton living in conventional dwellungs due to the report of the 2021 Census survey (in French).

3.2. Classification system

The Census 2021 data uses:

The NACE (revision 2) adopted in 2008;
The International Standard Classification of Occupations (ISCO-08);
The International standard classification of education (ISCED 2011)
The official geographical code (COG) as of January 1st, 2021 and the ISO code for countries.

3.3. Coverage - sector

Not applicable.

3.4. Statistical concepts and definitions

The information is given separately for each census topic.

3.4.1. Statistical concepts and definitions - Usual residence

The population comprises the persons having their usual residence on the territory. It includes homeless persons or persons usually residing in mobile homes registered in the territory of the municipality as well as inmates in the municipal penitentiary institutions. It is the statistical population comparable to the unduplicated population of previous censuses.

Usual residence : persons are registered where they spend most of the year, generally more than 6 months of the year.
The resident population of an area corresponds to:

persons living permanently in a dwelling in the area, including spouses who live away for professional reasons and pupils or students who are minors;
persons living in a community in the area (except for persons living in educational establishments housing school children or students (including military training establishments), or in penitentiary establishments
adults residing in an ‘educational’ community in the area;
persons detained in penitentiary establishments in the area;
homeless persons present in the area on the first day of the census;
persons who usually reside in mobile dwellings present in the area on the first day of the census;
boatmen.

Total population (cf. 3.4.1 Total population) is the sum of individuals whose usual residence is in metropolitan France (overseas territories are excluded for grid data) at the Census reference date (2021).
Here « total population » differs from the total population concept in French Census data, which include both usual and non usual residence, with double counts at the national level. In French Census data, the total population is the sum of the municipal population and the population counted separately.

3.4.2. Statistical concepts and definitions - Sex

Sex at the time of the survey (male / female).

3.4.3. Statistical concepts and definitions - Age

The age reached at the reference date (in completed years).

In the French Census, the reference date for the age is the first day of the survey (the third Thursday of January), and not the 1st January.

3.4.4. Statistical concepts and definitions - Marital status

Marriage and registered partnership:

In France, the marriage concerns opposite-sex and same-sex persons (Civil Code Title V, Art 143, modified by the law of 2013 which allows same-sex persons to marry). Since March 2005, a man and a woman may not marry before they reach the age of 18 (Civil Code Title V, Art 144). However, the public prosecutor of the place where the marriage is celebrated may grant age dispensations for serious reasons.
In France, a PACS is a contract concluded between two different-sex or same-sex natural persons, who have reached the age of majority, in order to organise their life together. (Civil Code, Title XIII, Art. 515-1)

Information about opposite-sex or same-sex marriage or registered partnership: in the French census, this information does not exist for married people or people in a registered partnership when they do not live together. By default, people in this situation are considered to be in an opposite-sex marriage or registered partnership. This solution has the advantage of not distorting the age structure of same-sex couples (contrarily to breakdown by shares of same-sex couples in couples living together) and does not lead to a significant overestimation of opposite-sex couples (+0.04 percentage point).

Divorce and dissolution of registered partnership:

Marriage is dissolved: 1. By the death of one of the spouses; 2. By a legally pronounced divorce. (Civil Code, Title V, Art. 227)
A PACS is dissolved by the death of one of the partners or by marriage of one or both of the partners. The PACS is also dissolved by a joint declaration of the partners or by a unilateral decision of either one (Civil Code, Title XIII, Art. 515-7).

In this respect (unilateral termination of the contract), the PACS does not meet the definition of "registered partnership" required by Eurostat. In reality, it does not effectively prevent a spouse from marrying or from engaging in another PACS. Moreover, the legal obligations associated with a PACS in France are much weaker than those for a marriage.
In the French census, dissolutions of registered partnerships are not recorded. Some dissolutions may be counted if people report them as a divorce, but it is potentially underestimated.

N.B. : no distinction can be made between legal and de facto marital status since in the French census, there is a single question on the marital status variable, with no distinction between legal and de facto status. For example, a divorced person who is now in a registered partnership would declare that they are in a registered partnership but can’t declare in the same time that the legal status is « divorced ».

Treatment of confidential data: in France, information about same-sex couples are confidential data. A swapping method has been applied to protect this information (cf. 7.2. Confidentiality – Data treatment).

3.4.5. Statistical concepts and definitions - Family status

A family is considered to be a setting able to receive one or more children. This is the part of a household made up of at least two persons and consisting of:

either a couple (consisting of two opposite-sex or same-sex persons, whether married or in a registered partnership, or two persons in a consensual union), with or without a child or children belonging to the same household;
or an adult with their child or children belonging to the same household (one-parent family).

For a person to be a child of a family, they must be single and not have a spouse or any children who are part of the same household.

A household can comprise zero, one or several families. Inside a household, an individual can either belong to one and only one family, or not belong to any family.

The links between members of a household are identified according to their link with the reference person.
The rule for determining the reference person in the household in complementary processing is as follows:

If the household comprises one or several families, at least one of which contains a couple, the reference person is the oldest active man among the men of these couples or, failing that, the oldest man;
If the household does not comprise any family containing a couple but at least one single-parent family, then the reference person is the oldest active person among the parents of single-parent families or, failing that, the oldest person;
If the household does not contain any families, the reference person is, excluding any paying guests or live-in employees, the oldest person of working age or, failing this, the oldest person.

Out of scope:

Persons living in an institutional household (workers' hostels, retirement homes, university residences, penitentiary establishments) or living in mobile dwellings (including boatmen);
Homeless persons.

3.4.6. Statistical concepts and definitions - Household status

The census in France uses the "household-dwelling" notion.
A household comprises all the occupants of a main residence, regardless of family ties. A household can consist of no families, one family or several families. A household made up of one person or a single family is a simple household, otherwise it is a complex household.

If the household comprises one or several families, at least one of which contains a couple, the reference person is the oldest active man among the men of these couples or, failing that, the oldest man;
If the household does not comprise any family containing a couple but at least one single-parent family, then the reference person is the oldest active person among the parents of single-parent families or, failing that, the oldest person;
If the household does not contain any families, the reference person is, excluding any paying guests or live-in employees, the oldest person of working age or, failing this, the oldest person.

The breakdown for household status also includes:

Persons living in an institutional household (workers' hostels, retirement homes, university residences, penitentiary establishments);
Persons living in mobile dwellings (including boatmen) and homeless persons (« persons not living in a private household but category not stated »).

3.4.7. Statistical concepts and definitions - Current activity status

In France, the declaration of the current activity status is not based on registers. The French census is declarative: measurement of employment and unemployment does not comply with the ILO (International Labour Office) definition.

In France (Labour Code, Title V, Art. L4153-1 to L4153-7), it is forbidden to employ workers under the age of sixteen, except in the case of:

Minors aged fifteen and older working under an apprenticeship contract;
General education students on information gathering visits organized by their teachers or, during the last two years of mandatory schooling, when they take part in observation periods;
Students in alternating work-school training or vocational training during the last two years of mandatory schooling, when they participate in introductory internships or training periods in a professional setting.

Minors over the age of fifteen are authorised during their school holidays to do work that is adapted to their age, provided they have effective rest periods equal to at least half the duration of their holidays.

Respondents are asked directly for their main activity. When there is an answer, the declaration is never challenged.

If there is no answer to this question, the adjustments use the responses provided in the rest of the questionnaire:

if the respondent provided indications concerning their job in one of the questions destined for persons working at the time of the census, and did not answer the questions concerning persons not working, then their main situation is adjusted by hot deck, taking respondents of the same sex and age group who answered questions concerning persons working as donors (if there are no donors, the main situation is considered to be "studying" for persons under the age of 20, "retired" for persons aged 55 and older, "unemployed" for men aged 20 to 54, "homemaker" for women aged 20 to 29 and "unemployed" for women aged "30 54");
if the respondent does not answer the questions addressed to persons working at the time of the census, but answers those addressed to persons not working, their situation is then adjusted by hot deck, taking those respondents of the same sex and age group who answered questions concerning persons not working as donors (if there are no donors, the main situation is considered to be "studying" for persons under the age of 20, "employed" for persons aged 20 to 64, and "retired" for persons of 65 years and older);
if the respondent does not answer the rest of the questionnaire concerning persons working or not working at the time of the census, then:
- their main situation is considered to be "employed", if the respondent checked "yes" to the question "are you currently employed?",
- otherwise, their main situation is considered to be "studying", if the respondent filled in a part of the zone devoted to enrolment in a higher education establishment and if they are under the age of 36,
- otherwise, their main situation is considered to be "other situation", if the respondent checked "no" to the question "are you currently employed?",
- otherwise, their main situation is adjusted by hot deck, taking persons of the same sex and age group as donors

And if there are no donors, the main situation is considered to be "studying" for persons under the age of 20, "employed" for persons aged 20 to 64, and "retired" for persons of 65 years old and older.

if the respondent filled in the rest of the questionnaire concerning persons working or not working at the time of the census, then their main situation is adjusted by hot deck, taking respondents of the same sex and age group and having answered the questions concerning persons working as donors (if there are no donors, the main situation is considered to be "studying" for persons under the age of 20, "employed" for persons aged 20 to 64, and "retired" for persons of 65 years and older").

3.4.8. Statistical concepts and definitions - Occupation

Occupation refers to the type of work done in a job (that is the main tasks and duties of the work). .
The breakdown by occupation is available for persons aged 15 or over who declare to be in employment at the time of the survey.
Persons under the age of 15 years, as well as persons aged 15 or over who declare to be unemployed at the time of the census are classified under 'not applicable'.

The categories included in the breakdown 'occupation' correspond to the major groups of the ISCO classification.

The Isco code is determined automatically from the occupation declared by individuals or from the code of professions and socio-professional categories.
However, in some cases, coding in Isco is not automatic. An Isco code was imputed on the basis of information from the labour force survey: a sequential simple random draw was carried out in order to achieve the proportions observed in the survey.

3.4.9. Statistical concepts and definitions - Industry

Industry (branch of economic activity) is the kind of production or activity of the establishment (or similar unit) in which the job of a currently economically active person is located.

The breakdown by industry is available for persons aged 15 or over who declare to be in employment at the time of the survey.
The categories included in the breakdown 'industry' list the 21 sections of the NACE Rev. 2 classification and appropriate aggregates.
Persons under the age of 15 years, as well as persons aged 15 or over who declare to be unemployed at the time of the census are classified under 'not applicable'.
The allocation of a person within the breakdowns of the topics 'Occupation', 'Industry' and 'Status in employment' is based on the same job.

3.4.10. Statistical concepts and definitions - Status in employment

Respondents in employment can declare themselves to be either own-account workers, salaried head of company, employees or helling a person at work without being paid.
Salaried heads of company are asked how many people they employ: if they have employees beside themselves, they are classified as employers. Otherwse, they are considered as own-account workers.

When there is an answer, the declaration is never challenged.

3.4.11. Statistical concepts and definitions - Place of work

The location of the place of work is the geographical area in which a currently employed person does his/her job. The place of work of those mostly working at home is the same as their usual residence. The term 'working' refers to work done as an 'employed person' as defined under the topic 'Current activity status'. 'Mostly' working at home means that the person spends all or most of the time working at home, and less time or any time in a place of work other than at home.

N.B. : Data from other overseas territories, called « overseas collectivities » are out of the field of the Census: Saint-Barthélemy, Saint-Pierre-et-Miquelon, Polynésie Française, Wallis-et-Futuna. However, people living in metropolitan France or in French overseas departments could work in an overseas collectivity (extra regio region). People could work and live there for less than 6 months in the year, or do remote work.

3.4.12. Statistical concepts and definitions - Educational attainment

Educational attainment' refers to the highest level successfully completed in the educational system of the country where the education was received. All education which is relevant to the completion of a level is taken into account even if this was provided outside schools and universities. Persons aged 15 years or over are classified under only one of the categories according to their educational attainment (highest completed level). Persons under the age of 15 years are classified under 'not applicable'.
In France, the breakdowns of the variable relative to educational attainment are not always consistent with the Isced nomenclature (two Isced codes could be possible for one given category in the French census). In this case, an Isced code was imputed on the basis of information from the labour force survey (where the disctinction between the 2 Isced codes is possible): a simple random draw was carried out in order to achieve the proportions observed in the survey.

3.4.13. Statistical concepts and definitions - Size of the locality

A locality is defined as a distinct population cluster, that is an area defined by population living in neighbouring or contiguous buildings. Such buildings may either: (a) form a continuous built-up area with a clearly recognisable street formation; or (b) though not part of such a built-up area, comprise a group of buildings to which a locally recognised place name is uniquely attached; or (c) though not meeting either of the above two criteria, constitute a group of buildings, none of which is separated from its nearest neighbour by more than 200 metres.

3.4.14. Statistical concepts and definitions - Place of birth

2 processing stages are conducted:

When the coding for the country of birth produces an "ambiguous" code, a process assigns a country's ISO code based on defined probabilities of correspondence between ambiguous codes and ISO codes. These probabilities take into account the population of the different countries. The appellations associated with ambiguous codes are: Africa, Asia, Europe, Oceania, America, British West Indies, North Africa, Channel Islands, Guianese, Dominican, Spanish African Territories or Canaries, Indochina, Kurd, New Guinea, Madeira or Azores, Serbia or Montenegro, Saint Martin, Tamil, Soviet Union, Virgin Islands.
If the country of birth is not filled in and the place of birth indicator shows "born in France", then the country of birth is assigned the code of a French territory based on the start of the code for the locality of birth.

If the country of birth is not filled in and the place of birth indicator shows "born abroad" then the country of birth is assigned:

the code of the nationality of birth of the individual who has become French, when this code corresponds to a foreign nationality;
the code of the foreign nationality of the individual who has not taken out French nationality;
in the absence of these 2 previous cases, the code of the country of birth of individuals having the same indicator of place of birth is assigned by hot deck (and the country "Algeria" is assigned if there is no donor).

The mother's place of usual residence is not used to fill in the place of birth."

Treatment of confidential data: in France, information about place of birth (people born in a foreign country) are confidential data. A swapping method has been applied to protect this information.

3.4.15. Statistical concepts and definitions - Country of citizenship

Citizenship is defined as the particular legal bond between an individual and his/her State, acquired by birth or naturalisation.

If the country of citizenship is not filled in, a processing stage is conducted:

the country of citizenship of individuals having the same place of birth (France or abroad) is assigned by hot deck, if the donnor has the French citizenship by birth ;
if the donnor is born abroad and has acquired the French citizenship or has a foreign citizenship, the country of birth of th individual is assigned.

Treatment of confidential data: in France, information about country of the citizenship (person who does not have the French citizenship) are confidential data. A swapping method has been applied to protect this information.

3.4.16. Statistical concepts and definitions - Year of arrival in the country

The year of arrival is the calendar year in which a person most recently established usual residence in the country. The data for 2021 refer to the time span between 1 January 2021 and the reference date.

Treatment of confidential data: in France, information about year of arrival in the country is a confidential data. A swapping method has been applied to protect this information.

3.4.17. Statistical concepts and definitions - Residence one year before

This indicates the relationship between the current place of usual residence and the place of usual residence one year prior to the census (on the 1st January 2020 for the Census 2021). Children under one year of age are classified under 'Not applicable'. Since in the French Census, the reference date for the age is the first day of the survey (on the third Thursday of January), children having 1 year between the 1st January and the third Thursday of January are also classified under 'Not applicable’. For all persons that have changed their usual residence more than once within the year prior to the reference date, the previous place of usual residence is the last usual residence from which they moved to their current place of usual residence.

3.4.18. Statistical concepts and definitions - Housing arrangements

The topic 'Housing arrangements' covers the whole population and refers to the type of housing in which a person usually resides at the time of the census. This covers all persons who are usual residents in different types of living quarters, or who do not have a usual residence and stay temporarily in some type of living quarters, or who are roofless, sleeping rough or in emergency shelters, when the census is taken. Occupants are persons with their usual residence in the places listed in the respective category.

‘Conventional dwellings' are structurally separate and independent premises at fixed locations which are designed for permanent human habitation and are, at the reference date, either used as a residence, or vacant, or reserved for seasonal or secondary use. 'Separate' means surrounded by walls and covered by a roof or ceiling so that one or more persons can isolate themselves. 'Independent' means having direct access from a street or a staircase, passage, gallery or grounds. 'Other housing units' are huts, cabins, shacks, shanties, caravans, houseboats, barns, mills, caves or any other shelter used for human habitation at the time of the census, irrespective if it was designed for human habitation. - 'Collective living quarters' are premises which are designed for habitation by large groups of individuals or several households and which are used as the usual residence of at least one person at the time of the census.

'Occupied conventional dwellings', 'other housing units' and 'collective living quarters' together represent'‘living quarters'. Any 'living quarter' must be the usual residence of at least one person. The sum of occupied conventional dwellings and other housing units represents 'housing units'.

The homeless (persons who are not usual residents in any living quarter category) can be persons living in the streets without a shelter that would fall within the scope of living quarters (primary homelessness) or persons moving frequently between temporary accommodation (secondary homelessness).

3.4.19. Statistical concepts and definitions - Type of family nucleus

A family is considered to be a setting able to receive one or more children. This is the part of a household made up of at least two persons and consisting of:

either a couple (consisting of two opposite-sex or same-sex persons, whether married or in a registered partnership, or two persons in a consensual union), with or without a child or children belonging to the same household;
or an adult with their child or children belonging to the same household (one-parent family).

For a person to be a child of a family, they must be single and not have a spouse or any children who are part of the same household.

A household can comprise zero, one or several families. Inside a household, an individual can either belong to one and only one family, or not belong to any family.

If the household comprises one or several families, at least one of which contains a couple, the reference person is the oldest active man among the men of these couples or, failing that, the oldest man;
If the household does not comprise any family containing a couple but at least one single-parent family, then the reference person is the oldest active person among the parents of single-parent families or, failing that, the oldest person;
If the household does not contain any families, the reference person is, excluding any paying guests or live-in employees, the oldest person of working age or, failing this, the oldest person.

Out of scope:

Persons living in an institutional household (workers' hostels, retirement homes, university residences, penitentiary establishments) or living in mobile dwellings (including boatmen)
Homeless persons

3.4.20. Statistical concepts and definitions - Size of family nucleus

A family is considered to be a setting able to receive one or more children. This is the part of a household made up of at least two persons and consisting of:

either a couple (consisting of two opposite-sex or same-sex persons, whether married or in a registered partnership, or two persons in a consensual union), with or without a child or children belonging to the same household;
or an adult with their child or children belonging to the same household (one-parent family).

For a person to be a child of a family, they must be single and not have a spouse or any children who are part of the same household.

A household can comprise zero, one or several families. Inside a household, an individual can either belong to one and only one family, or not belong to any family.

If the household comprises one or several families, at least one of which contains a couple, the reference person is the oldest active man among the men of these couples or, failing that, the oldest man;
If the household does not comprise any family containing a couple but at least one single-parent family, then the reference person is the oldest active person among the parents of single-parent families or, failing that, the oldest person;
If the household does not contain any families, the reference person is, excluding any paying guests or live-in employees, the oldest person of working age or, failing this, the oldest person.

Out of scope:

Persons living in an institutional household (workers' hostels, retirement homes, university residences, penitentiary establishments) or living in mobile dwellings (including boatmen);
Homeless persons.

3.4.21. Statistical concepts and definitions - Type of private household

A family is considered to be a setting able to receive one or more children. This is the part of a household made up of at least two persons and consisting of:

either a couple (consisting of two opposite-sex or same-sex persons, whether married or in a registered partnership, or two persons in a consensual union), with or without a child or children belonging to the same household;
or an adult with their child or children belonging to the same household (one-parent family).

For a person to be a child of a family, they must be single and not have a spouse or any children who are part of the same household.

A household can comprise zero, one or several families. Inside a household, an individual can either belong to one and only one family, or not belong to any family.

If the household comprises one or several families, at least one of which contains a couple, the reference person is the oldest active man among the men of these couples or, failing that, the oldest man;
If the household does not comprise any family containing a couple but at least one single-parent family, then the reference person is the oldest active person among the parents of single-parent families or, failing that, the oldest person;
If the household does not contain any families, the reference person is, excluding any paying guests or live-in employees, the oldest person of working age or, failing this, the oldest person.

N.B. : the breakdown « couples without resident children » only applies to couples living together (2 persons), but not couples living with other people (ascendants for example).

Out of scope:

Persons living in an institutional household (workers' hostels, retirement homes, university residences, penitentiary establishments) or living in mobile dwellings (including boatmen);
Homeless persons.

3.4.22. Statistical concepts and definitions - Size of private household

A family is considered to be a setting able to receive one or more children. This is the part of a household made up of at least two persons and consisting of:

either a couple (consisting of two opposite-sex or same-sex persons, whether married or in a registered partnership, or two persons in a consensual union), with or without a child or children belonging to the same household;
or an adult with their child or children belonging to the same household (one-parent family).

For a person to be a child of a family, they must be single and not have a spouse or any children who are part of the same household.

A household can comprise zero, one or several families. Inside a household, an individual can either belong to one and only one family, or not belong to any family.

If the household comprises one or several families, at least one of which contains a couple, the reference person is the oldest active man among the men of these couples or, failing that, the oldest man;
If the household does not comprise any family containing a couple but at least one single-parent family, then the reference person is the oldest active person among the parents of single-parent families or, failing that, the oldest person;
If the household does not contain any families, the reference person is, excluding any paying guests or live-in employees, the oldest person of working age or, failing this, the oldest person.

Out of scope:

Persons living in an institutional household (workers' hostels, retirement homes, university residences, penitentiary establishments) or living in mobile dwellings (including boatmen);
Homeless persons.

3.4.23. Statistical concepts and definitions - Tenure status of households

The topic 'Tenure status of households' refers to the arrangements under which a private household occupies all or part of a housing unit.
The French census is declarative and for housing issues, only one person of the household answers to the questions.

Households that are in the process of paying off a mortgage on the housing unit in which they live or purchasing their housing unit over time under other financial arrangements are classified under 'Households of which at least one member is the owner of the housing unit'.
Households that are tenants or sub-tenants are classified in the category « Households of which at least one member is a tenant of all or part of the housing unit (and no other member is the owner) ».
Households that are housed free of charge are classified in the category « Households occupying all or part of a housing unit under some other form of tenure ».

Out of scope: institutional houselholds, households living in mobile dwellings and homeless persons.

3.4.24. Statistical concepts and definitions - Type of living quarter

A living quarter is housing which is the usual residence of one or more persons.

‘Conventional dwellings’ are structurally separate and independent premises at fixed locations which are designed for permanent human habitation and are, at the reference date, either used as a residence, or vacant, or reserved for seasonal or secondary use.

'Separate' means surrounded by walls and covered by a roof or ceiling so that one or more persons can isolate themselves. 'Independent' means having direct access from a street or a staircase, passage, gallery or grounds.

'Other housing units' are huts, cabins, shacks, shanties, caravans, houseboats, barns, mills, caves or any other shelter used for human habitation at the time of the census, irrespective if it was designed for human habitation.
'Collective living quarters' are premises which are designed for habitation by large groups of individuals or several households and which are used as the usual residence of at least one person at the time of the census. 'Occupied conventional dwellings', 'other housing units' and 'collective living quarters' together represent'‘living quarters'. Any 'living quarter' must be the usual residence of at least one person.

3.4.25. Statistical concepts and definitions - Occupancy status

‘Occupied conventional dwellings’ are conventional dwellings which are the usual residence of one or more persons at the time of the census. ‘Unoccupied conventional dwellings’ are conventional dwellings which are not the usual residence of any person at the time of the census.

The category of the dwelling is determined by the enumerator based on the information collected in the neighbourhood if the dwelling is vacant, and in accordance with the following definitions:

a secondary dwelling is a dwelling that is occupied only during a part of the year (less than 6 months per year), at weekends, during holidays and leisure time;
the occasional dwellings are classified with secondary residences. These dwellings - or self-contained rooms - are occasionally used for professional purposes by a person who also has a familial dwelling;
a vacant dwelling is unoccupied and is in one of the following cases: available for sale or rent (new or old), already allocated to a buyer or a tenant and waiting to be occupied, in the course of being settled in succession law, having no precise use (in a state of disrepair but habitable), preserved by an owner for future use by one of his/her employees, parents or friends, uninhabited following departure of the occupant for a community (retirement home, hospital for a long stay, etc.).

If the category of the dwelling is undetermined or if there is any inconsistency between the category of the dwelling and the number of occupants, the following processing rules are applied:

if the dwelling has no occupants and has been classified as a main residence or if its dwelling category is not filled in, it shall be assigned the dwelling category of a donor from among ordinary unoccupied dwelling.

[in the absence of donors, the dwelling shall be classified as a secondary dwelling];

if the dwelling has at least one occupant and has been classified as an occasional, vacant or secondary dwelling, or if its category is not filled in, it shall be classified as a main residence."

3.4.26. Statistical concepts and definitions - Type of ownership

The topic ‘Type of ownership’ refers to the ownership of the dwelling and not to that of the land on which the dwelling stands. It is intended to show the tenure arrangements under which the dwelling is occupied.

‘Owner-occupied dwellings’ are those where at least one occupant of the dwelling owns parts or the whole of the dwelling.
‘Rented dwellings’ are those where at least one occupant pays a rent for the occupation of the dwelling, and where no occupant owns parts or the whole of the dwelling.

Unoccupied conventional dwellings and secondary dwelling (a dwelling that is occupied less than 6 months per year) are classified under ‘Not applicable’.

Out of scope: institutional dwellings, mobile dwellings and homeless persons.

3.4.27. Statistical concepts and definitions - Number of occupants

The number of occupants of a housing unit is the number of people for whom the housing unit is the usual residence.

3.4.28. Statistical concepts and definitions - Useful floor space

The "Number of rooms" concept was used.

3.4.29. Statistical concepts and definitions - Number of rooms

The "occupied rooms" concept includes bedrooms, dining rooms, lounges, living rooms, studios. They are counted regardless of their size, as is staff accommodation (and other additional rooms) not allocated to third parties. It does not include halls, corridors, bathrooms, closets, alcoves, toilets, laundry rooms, pantries, etc. nor any rooms used exclusively for work purposes. The kitchen is considered as an occupied room if it measures more than 12 m².

3.4.30. Statistical concepts and definitions - Density standard (floor space)

The "Number of rooms" concept was used.

3.4.31. Statistical concepts and definitions - Density standard (number of rooms)

The density standard was calculated by dividing the number of rooms in the dwelling by the number of occupants.

3.4.32. Statistical concepts and definitions - Water supply system

Water supply system: the question is only asked in Overseas territories (cf. ‍13.1.32. Water supply system).

3.4.33. Statistical concepts and definitions - Toilet facilities

Toilet facilities: the question is only asked in Overseas territories (cf. ‍13.1.33. Toilet facilities).

3.4.34. Statistical concepts and definitions - Bathing facilities

A bathing facility is any facility designed to wash the whole body and includes shower facilities.

3.4.35. Statistical concepts and definitions - Type of heating

A housing unit is considered as centrally heated if heating is provided either from a community heating centre or from an installation built in the building or in the housing unit, established for heating purposes, without regard to the source of energy.

3.4.36. Statistical concepts and definitions - Type of building

The topic 'Dwellings by type of building' refers to the number of dwellings in the building in which the dwelling is placed.

3.4.37. Statistical concepts and definitions - Period of construction

The topic 'Dwellings by period of construction' refers to the year when the building in which the dwelling is placed was completed.

3.5. Statistical unit

The EU programme for the 2021 population and housing censuses includes data on persons, private households, family nuclei, conventional dwellings and living quarters.

3.6. Statistical population

Persons enumerated in the 2021 census are those who were usually resident in the territory of the reporting country at the census reference date. Usual residence means the place where a person normally spends the daily period of rest, regardless of temporary absences for purposes of recreation, holidays, visits to friends and relatives, business, medical treatment or religious pilgrimage.

3.7. Reference area

Data are available at different levels of geographical detail: national, NUTS2, NUTS3 and local administrative units (LAU2).

3.8. Coverage - Time

Data refer to the situation in the reporting country at the census reference date (see item 5).

3.9. Base period

Not applicable.

Counts of statistical units should be expressed in numbers and where is needed rate per inhabitants enumerated in the country.

See the following sub-concepts.

5.1. EU census reference date

1 January 2021

5.2. National census reference date

1 January 2020

5.3. Differences between reference dates of national and EU census publications

National census results will be disseminated in June 2024.
EU census results were produced before this date (delivery in March 2024).
EU census results are thus based on 2020 national census results and then adjusted to the 2021 municipal populations.

6.1. Institutional Mandate - legal acts and other agreements

At national level:

The law of 27 February 2002 on local democracy (title V, articles 156 to 158) sets the objectives of the population census:

the publication each year of the legal population figures (municipal population, population counted separately and total population). These figures are calculated for France, all its municipalities and administrative districts. Insee is responsible for calculating the legal populations;
description of the demographic and social characteristics of the population;
enumeration and description of characteristics of dwellings.

The law nº 2002-276 of 27 February 2002 founds also the principles of execution of the census.

The main other legal texts are:

Decree in Council of State nº 2003-485 of 5 June 2003 defining the methods of application of the law;
Order of 26 June 2003 authorising the collection of information from people living in communities;
Order of 19 July 2007 governing the dissemination of the results of the population census, updated in March 2024.

At European level, for 2021 Census:

6.1.1. Bodies responsible

The census on population and housing is conducted under the responsibility and control of the State (law of 27 February 2002 on local democracy).

The municipality or the public inter-municipality cooperation establishments (EPCI) are required by law to prepare and conduct the census surveys and therefore receive financial allowance from the State.

Insee’s mission is to organise the collection of the information and ensure the quality of the collected information. It gathers the collected information, processes the questionnaires and disseminates the results.

Enumerators recruited by the municipality or EPCI drop off the questionnaires and pick them back up once they have been filled in. People living in institutions such as military quartering, hospitals, etc. are surveyed by Insee.

6.2. Institutional Mandate - data sharing

Eurostat data collection and data production.

7.1. Confidentiality - policy

At the national level, Article 6 of Law No. 51-711 of 7 June 1951, as amended, on the obligation, coordination and secrecy of statistics determines what statistical secrecy is, its limits and the conditions for its application.

Generally speaking, as regards access to public data, confidentiality obligations relating to the protection of privacy or business secrecy and the protection of personal data are guaranteed by law (Article 1 of the Law for a Digital Republic).

A Statistical Confidentiality Committee ensures that these statutory guarantees are maintained.

The answers to the annual census survey questionnaire are protected by statistical secrecy and are intended for INSEE. Their use and access are strictly controlled and limited to the preparation of statistics or research work. In particular, surnames and first names are not kept beyond 31 December of the year following the survey.

The General Regulation 2016/679 of 27 April 2016 on data protection (RGPD) and Law No. 78-17 of 6 January 1978 on information technology, files and freedoms apply to this survey.

Enumerated people may exercise a right of access, rectification or limitation of processing for data concerning them during the period of conservation of identification data.

Rules on the dissemination of the results of the population census are set out in the Order of 19 July 2007 which specifically indicates geographical levels (and size) for distribution, the list of sensitive variables and the possible forms of products (maps, tables, detailed files).

In the version in force at the time of delivery of the data, four variables are defined as sensitives: place of birth, country of citizenship, year of arrival in France, place of usual residence one year prior to the census. At the moment, same-sex couples are also defined as sensitives.

7.2. Confidentiality - data treatment

The issue of confidentiality was applied to the variables "Country of citizenship", "Place of birth", "Year of arrival in France", "Place of usual residence one year prior to the census" as their diffusion is strictly regulated in France by the decree of 19 July 2007 on the dissemination of the results of the population census. Moreover, the issue of confidentiality was applied to same-sex couples, as their dissemination has just been regulated (decree of 19 July 2007, modified in March 2024).

For other issues, confidentiality is ensured by sampling, as most hypercubes are based on the “complementary” use.

To ensure confidentiality for these variables, the French INS applied two methods: one for the hypercubes and one for the grid data (cf. metadata on grid data).

Hypercubes: the French INS applied a target record swapping (TRS) method which consists in swapping sensitives persons with no sensitives persons between two municipalities (in the same NUTS2 / NUTS3, or not). This swapping is based on similarities between individuals, in order to exhange individuals resemble each other, beyond their sensitive characteristics.

Two types of risks are defined:

Re-identification risk: small cells on sensitive variables have to be protected (individuals born abroad, individuals with a foreign country of citizenship, individuals who immigrated, individuals in a same-sex couple).
Attribute disclosure control risk: moreover, cells with more than 80% of its population with a sensitive attribute require a protection too.

Identification of sensitive individuals: keys were defined from sex and age variables, crossed with sensitive variables for each relevant geographical levels. If there are cases with very few individuals for this cross of variables, they must be protected. We set a threshold of 10 individuals.
Swapping: sensitive individuals are swapped with no sensitive ones, who have the same socio-demographic variables, as far as possible (sex, age, education level, activity status, type of area, family composition and the sample weight rounded to the unit). If the risk was identified at the municipality level, individuals were swapped between two municipalities in the same NUTS3 level. But if the risk was identified at the NUTS3 level, individuals were swapped between two municipalities in different NUTS3 level and in the same NUTS2 level, etc.

8.1. Release calendar

A schedule for the release of census results is publicly available on insee.fr : Census results: timing and outputs.

In France, the legal 2021 populations have been disseminated in December 2023.
Detailed databases will be disseminated in June 2024.
Sub-municipal results (including grid data) will be disseminated in October 2024.

8.2. Release calendar access

Census results: timing and outputs

8.3. Release policy - user access

Internet users can find all the available statistical data free of charge on the INSEE website, as well as the information needed to interpret them correctly.

Important actions are carried out to meet the expectations of the media, which are essential relays to a wider public.

The results of the population censuses.

Data on population and housing censuses are disseminated every decade.
Data on population by grid cell are disseminated for the first time for the 2021 Census.

See the following sub-concepts.

10.1. Dissemination format - News release

A press conference is held every year in January to inform about the launch of the data collection. On this occasion, a press kit is distributed. It specifies the procedures for the survey and announces the results of the previous year's demographic survey.

10.2. Dissemination format - Publications

An Insee Première and regional studies are published when the detailed results are released in June.

10.3. Dissemination format - online database

Online databases are available:

Detailed figures and related databases;
Detailed tables and associated databases;
Mobility flow databases;
Sub-municipal databases;
Detailed files.

10.4. Dissemination format - microdata access

Individual files are made available to users outside INSEE after review by the Statistical Confidentiality Committee, via the Secure Data Access Centre (CASD).

The Quetelet Progedo network has detailed files available on the INSEE website.

10.5. Dissemination format - other

The interactive mapping tool on statistiques-locales.insee.fr allows the results of the census to be viewed at different geoographic scales. It proposes 2018 results, in comparison if possible with 2013 and 2008 results, but also historical series. All indicators were recalculated at constant geographical perimeter, in the geography in force on 1 January 2021.

A skills centre handles complex requests for population censuses (RP) from Insee contact.

10.6. Documentation on methodology

The methodology of the population census was renewed in 2004 and resulted in an Insee méthodes « Pour comprendre le recensement de la population » in 2005.

The quality of population estimates in the census also led to an Insee Méthodes in 2020.

The documentation also consists of thematic advice sheets, technical notes and sheets on data processing after collection. They present the information you need to know in order to make the best use of the census results. They are available on insee.fr.

10.7. Quality management - documentation

Cf. 10.6. Documentation on methodology.

11.1. Quality assurance

Since 2005, the European Statistics Code of Practice has been the benchmark for assessing the quality of the output of national statistical institutes. Periodic reviews by European peers are organised to ensure that the principles of this reference framework are implemented and to ensure that each institute is committed to continuous improvement. Within this framework, INSEE adopted a process-based approach. A range of tools, pooled within the Official Statistical Service (SSP), were created to describe statistical production processes, analyse their strengths and weaknesses, assess the risks involved, examine their documentation (metadata) or provide expert appraisal of a particular stage (analysis of user needs, data validation, etc.). The diagnoses resulting from these « quality approach » lead to the establishment of action plans that are regularly monitored in the context of « process review ». In addition, INSEE regularly conducts satisfaction surveys on the indicators and data it produces. The results of these surveys are available on the insee.fr website.

In addition, with regard to surveys carried out by public statistics producing services (INSEE, ministerial statistical services, other related bodies such as INED, Céreq, Inserm, etc.), the Label Committee is responsible for examining, on behalf of the National Council for Statistical Information (CNIS), all projects for which the approval provided for in Article 2 of the Law of 7 June 1951 is requested. Over time, the Committee has developed a method and an experience for examining the files submitted to it. Starting from considerations expressed in terms of the burden or proportionality of the collection to the objectives pursued, the Committee extended its examination rules to cover all dimensions of statistical quality, as formalised in the European Statistics Code of Practice. For the SSP, the Label Committee thus constitutes a lever for ensuring compliance with these principles, in terms of consultation, methodological quality, proportionate burden, dissemination or availability of duly documented statistical sources.

On a more strategic level, the INSEE Inspectorate General carries out evaluations, assessments and audits of the Institute's work, its operations and the organisation of its services. Some of these missions focus more specifically on INSEE's key processes.

11.2. Quality management - assessment

Cf. below.

11.2.1. Coverage assessment

The quality of a census mostly depends on the quality of data collection. The French census method ensures good quality, precisely because it is conducted annually and by survey. These two original features mean that the collection burden is spread out over time and that the different players develop their skills compared to a decennal exhaustive Census. The French Census method also ensures to cover all population fields and not only those appearing in the administrative data.

Moreover, each of the ingredients involved in elaborating the results of the census is validated progressively as it is implemented. In addition to these data checks (collected or administrative), different operations verify the processing. For example:

In municipalities of 10,000 residents and more, which are surveyed every year by means of a survey, the quality of the survey depends in part on the exhaustivity of the localised buildings register (RIL). This register is used for collection and for population estimates. The RIL is updated every year, both by Insee and the municipalities. Moreover, national survey operations measuring the quality of the RIL have been organised on several occasions since 2004 (every two years on average) to check the match between the RIL and the ground. In practice, they have conducted exhaustive "combing" of a certain amount of districts (IRIS), thus ensuring good coverage of the survey address base.
In municipalities of fewer than 10,000 residents, the exhaustivity of dwellings is checked on the ground before each survey.
To ensure collection quality, all players receive proper training (enumerators, municipal coordinators, supervisors and INSEE personnel). Next, as soon as the questionnaires are available, different indicators are checked in the INSEE offices and a score is assigned to each municipality in the census. If the score is insufficient, INSEE operators conduct checks on the ground. These checks can lead to correcting the questionnaires, in collaboration with the municipalities concerned, thus contributing to improving the collection and verification protocols.
The non-response is very low (less than 4%) and methods for dealing with non-response are applied.
The quality of data entry is checked each year: a sample of questionnaires (between 5,000 and 6,000) is double-entered, one by the usual service provider and the other by a competitor. The INSEE analyses differences between the two entries for each question and deduces error rates that can be assigned to the main service provider. This double entry of data is conducted in the course of the entry campaign, ultimately enabling correction of protocols for the following batches (all questionnaires are distributed each year into twenty batches).
The population estimates are subjected to consistency and likelihood checks, and then assessed (for example, to identify atypical trends).
Operations are also conducted regularly (5 operations since 2004) on coding quality for the fields "employer activity" and "occupation", by comparing competing codings for a sub-sample of 100,00 individual questionnaires. An assessor then examines all diverging codings and 10% of converging codings. The assessor knows the first two codings assigned and can choose between them, or propose a different, third coding. The assessor''s proposal is considered to be correct. Error rates in coding are thus demonstrated to be of an acceptable level and regularly reduced through time. The results also facilitate improvement of automatic coding tools and the instructions for manual corrections of coding failures in regional offices.

11.2.2. Post-enumeration survey(s)

Cf. 11.2.1. Quality management - Coverage assessment.

12.1. Relevance - User Needs

The census data disseminated by Eurostat are addressed to policy makers, researchers, media and the general public.

12.2. Relevance - User Satisfaction

In France, a survey on the dissemination of legal populations was conducted from 27 December 2018 to 11 January 2019 among Internet users visiting the legal populations pages of the insee.fr website.

A survey on the dissemination of statistical results of population census was conducted from 25 June 2019 to 24 July 2019 among Internet users visiting the census pages of the insee.fr website.

Dissemination of legal populations (results of the survey conducted in 2018).

At the european level, no user satisfaction surveys are carried out. User inquiries are handled by the Eurostat User Support service.

12.3. Completeness

The French census operation complies with the regulatory requirements specified in the section 6. Institutional mandate.

13.1. Accuracy - overall

A fact sheet on the accuracy of census results is available.

The accuracy of census results (Topic Sheet, March 2017) (pdf, fr, 350 Ko, 26 April 2022)
Population census: The accuracy of the population figure in the major metropolitan areas (pdf, fr, 105 Ko, 26 April 2022)
The quality of population estimates in the census (Insee Méthodes n°136 - October 2020)

13.1.1. Overall accuracy - Usual residence

There are no particular reasons for data unreliability for this topic.

13.1.2. Overall accuracy - Sex

There are no particular reasons for data unreliability for this topic.

13.1.3. Overall accuracy - Age

Data relating to individuals aged 100 years or over are not reliable. Some corrections are made for the age variable, but it is not sufficient to resolve all the inconsistencies in the questionnaire

13.1.4. Overall accuracy - Marital status

In some cases, the answers of the questioned persons may differ from the real legal situation. For example, a person who lives separately from their spouse but who is not yet divorced, and therefore legally married, may hesitate between "single", "married" and "divorced".
In the French census, dissolutions of registered partnership are not entered. Some dissolutions may be counted if people report them as a divorce, but it is potentially underestimated.

Treatment of confidential data: in France, information about same-sex couples is a confidential data. A swapping method has been applied to protect this information.

13.1.5. Overall accuracy - Family status

Inaccuracy is linked to the complementary processing sampling rate: the results in municipalities with a population of 2,000 or less may be fragile.

13.1.6. Overall accuracy - Household status

Inaccuracy is linked to the complementary processing sampling rate: the results in municipalities with a population of 2,000 or less may be fragile.

13.1.7. Overall accuracy - Current activity status

Employment and unemployment don’t correspond to the ILO concept (cf. 3.4.7).

Data on individuals aged 85 years or over who are declared in the labour force (employed or unemployed) are not reliable.

13.1.8. Overall accuracy - Occupation

The coding stage can generate some defects in terms of quality.

In census questionnaires persons fill out a title for their occupation. Several questions enable the coding of the occupation to be fine-tuned: establishment where the occupation is exercised, own-account or salaried worker, number of employees for own-account workers, function and occupational position of employees.

Based on these titles and additional information, the occupation and socio-professional category are then coded using automatic coding software. About one quarter of cases cannot be coded automatically: the software does not recognize the appellation of the occupation or finds inconsistencies between this appellation and the additional information. Coding is then done "manually" by agents who assign a code based on all the available information.

Coding in ISCO nomenclature

The French census codes occupations in the 2003 Nomenclature of Occupations and Socio-Professional Categories (PCS).
Occupations has been coded in ISCO nomenclature :
- the coding was automatic in 70 % of cases;
- the Isco code has been imputed in the other cases, based on the Continuous Labour Force Survey data.
There may be a slight lack of precision for these imputed codes.

Added inaccuracy is linked to the complementary processing sampling rate: the results in municipalities with a population of 2,000 or less may be fragile.

13.1.9. Overall accuracy - Industry

The coding stage can generate defects in terms of quality.

Coding of the activity of the employer establishment is based on the appellation filled in by the respondent. This is done by means of an automatic comparison with a reference list of appellations. This coding is completed by coding based on two items (the respondent's declaration of the appellation or corporate name of the employer establishment and of its address) that enable the establishment to be identified in a database containing all the active establishments on the reference date for collection of the census, and establishments in border countries (Germany, Belgium, Luxembourg, Switzerland and Monaco).

Added inaccuracy is linked to the complementary processing sampling rate: the results in municipalities with a population of 2,000 or less may be fragile.

13.1.10. Overall accuracy - Status in employment

Inaccuracy is linked to the complementary processing sampling rate: the results in municipalities with a population of 2,000 or less may be fragile.

13.1.11. Overall accuracy - Place of work

In the case of an incomplete or inaccurate response

If the workplace municipality is incomplete or misspelt and corresponds to that of another existing municipality, the latter municipality is registered, even if it is located outside the department of residence. This can lead to a small number of erroneous situations that are difficult to correct because it is not always easy to distinguish them from situations of real distance.
If the workplace municipality is not filled in, thus it is adjusted by hot-deck, or by the usual residence if there is no donor.
If neither the workplace department nor municipality is filled in, then the workplace municipality is adjusted by imputation.

The case of "border" municipalities

For the purposes of local studies, in five border countries (Germany, Belgium, Luxembourg, Monaco and Switzerland), the workplace municipality is coded if it is part of a list of municipalities considered to be "border" municipalities. These are the countries with which there is the most significant commuting. This information is sometimes fragile because respondents who work abroad do not always fill in the workplace municipality. In that case a workplace municipality is automatically assigned, generally in France.

Added inaccuracy is linked to the complementary processing sampling rate: the results in municipalities with a population of 2,000 or less may be fragile.

13.1.12. Overall accuracy - Educational attainment

The coding stage can generate some defects in terms of quality.

Coding in ISCED nomenclature

The French census collects information on completed degrees, and not the level of education. This leads to difficulties :

in estimating ISCED 1 (primary education) and 2 (lower secondary education);
and in estimating ISCED 3 (upper secondary education) and 4 (post-secondary non-tertiary education).

To compensate for these conceptual differences, additional information was obtained from the Continuous Labour Force Survey, which provides more precise information on the level of education.

In the French census, one category of degree can be broken down into Isced 1 or Isced 2. For theses individuals, a random selection was made to allocate them into Isced 1 or Isced 2, on the basis of the proportions of persons in Isced 1 and Isced 2 in the Labour Force Survey.
The same applies to an other category of degree in France, that can be broken down into Isced 3 or Isced 4. For theses individuals, a random selection was made to allocate them into Isced 3 or Isced 4, on the basis of the proportions of persons in Isced 3 and Isced 4 in the Labour Force Survey.

There may be a slight lack of precision for these imputed codes.

Added inaccuracy is linked to the complementary processing sampling rate: the results in municipalities with a population of 2,000 or less may be fragile.

13.1.13. Overall accuracy - Size of the locality

There are no particular reasons for data unreliability for this topic.

13.1.14. Overall accuracy - Place of birth

There are no particular reasons for data unreliability for this topic.

13.1.15. Overall accuracy - Country of citizenship

There are no particular reasons for data unreliability for this topic.

13.1.16. Overall accuracy - Year of arrival in the country

The French census does not collect information on successive periods of immigration and therefore on residence abroad. The data collection provides knowledge of the year of arrival in France, based on the respondent's declaration if they are born abroad. Because the rate of non-response for this variable is in excess of 20%, no adjustment is made to the year of arrival in France.

For persons born in France, the year of arrival after a potential period out of France is unknown.

13.1.17. Overall accuracy - Residence one year before

Data on individuals aged 85 years or over who are declared in the labour force (employed or unemployed) are not reliable.

13.1.18. Overall accuracy - Housing arrangements

There are no particular reasons for data unreliability for this topic.

13.1.19. Overall accuracy - Type of family nucleus

Inaccuracy is linked to the complementary processing sampling rate: the results in municipalities with a population of 2,000 or less may be fragile.

13.1.20. Overall accuracy - Size of family nucleus

Inaccuracy is linked to the complementary processing sampling rate: the results in municipalities with a population of 2,000 or less may be fragile.

13.1.21. Overall accuracy - Type of private household

Inaccuracy is linked to the complementary processing sampling rate: the results in municipalities with a population of 2,000 or less may be fragile.

13.1.22. Overall accuracy - Size of private household

Inaccuracy is linked to the complementary processing sampling rate: the results in municipalities with a population of 2,000 or less may be fragile.