Population and Housing Census 2001.
02.01. Population structure. Population and Housing Census 2001.
Population and housing censuses are normally conducted every tenth year, usually in years ending with 0.
The whole country, regions, counties, municipalities, urban districts, statistical tracts and basic (statistical) units.
Division for Population and Housing Census.
The Population and Housing Census 2001 is pursuant to the Statistics Act, the Land Subdivision Act (about the survey, registration and division of land) and the Population Registration Act. Every person who received the form was obliged to respond.
On 3rd November 2001, Statistisk sentralbyrå (Statistics Norway) carried out a Population and Housing Census in Norway (Census 2001). The purpose for this nation-wide census is to illustrate how people live in Norway, provide information on the composition of the population and describe living conditions in the Norwegian society.
Population and housing censuses have a long history in Norway. The first census was conducted in 1769 and the 2001 Census is the 21st.
In the 2001 Census, both registers and questionnaires were used to gather information. Data from the census is also used to supplement and update the Central Population Register (CPR) and the Register of Ground Properties, Addresses and Buildings (GAB). In future, it will therefore be possible to gather all census data from various administrative and statistical registers and questionnaires will no longer be needed.
The Population and Housing Census 2001 comprises all persons, including foreign citizens, who were considered resident in Norway, according to the Central Population Register on 3rd November 2001, census day.
The main rule in population registration is that a person is to be registered as resident at the address where the person spends the majority of his or her daily night-rest. However there are some exceptions, the most important being that unmarried pupils and students are to be registered as resident at the address at which they were living before moving to their place of study1. Moreover, married persons and persons with their own children in the same household are to be registered as living with their spouse or children even though they might be, for e.g., weekly commuters.
The census basically comprises all private households and private dwellings where at least one person was registered as resident on 3rd November 2001. Information was not gathered on dwellings of people being cared for in old people's homes, nursing homes, orphanages or other institutional households. However, information about place of usual residence was gathered for students and people dwelling in old people's homes and nursing homes.
Information on persons is retrieved from the Central Population Register (CPR) and several other registers. Information on persons composing one family and one household is based on joint information from the CPR and the housing form. Information on housing and buildings is mainly gathered from the housing form but is also supplemented with information from the GAB register.
The Population and Housing Census 2001 was a full count.
The register data used in the Population and housing census 2001 (Census 2001) is the same as that used by Statistics Norway in other statistics. Statistics Norway has built up data systems referred to as statistical registers in several statistical areas (sectors). These are again based upon one or more administrative data systems that are either administrative registers held by other public authorities or administrative data collected by Statistics Norway.
The population statistics system at Statistics Norway (Besys) is the most central register in Census 2001. The most important source of data is the Central Population Register. Demographic information and information on place of residence and immigration background are retrieved from Besys.
Labour market data is based on several registers. The most important ones are The Register of Employees, The Register of End of the Year Certificates (Register of Wage Sums), The Register for Personal Tax Payers, The Register of Unemployed and The Central Co-ordinating Register for Legal Entities (business register).
The Register of Employees is the main source for data on salaried employees, but The Register of Wage Sums gives additional information. These are both job-registers. The tax register is the main source of data on self-employed persons. The Register of Unemployed holds data on unemployed persons and persons in labour market measures. The business register holds information on the working places. Several registers give additional information: register of conscripts, registers of employees in central and local government, register of sick leave etc.
Labour market variables are based on several different sources. Statistics Norway has established a system to jointly utilise these. The systems comprise modules for consistency management between various data sources, selection of the most important job and classification as person employed.
This source is Statistics Norway's Register of the Population's Highest Level of Education (BHU).
This register is based on information from individual educational institutions and state and county- municipal data systems. The register contains information on highest completed education and ongoing education (pupils and students).
The main source of income data is the personal tax return obtained from the Directorate of Taxes. In addition, this data is linked to income data from the following sources: Tax statistics for personal taxpayers, Register of wage sums, Register of social assistance, data from the National Insurance Administration, from the State Education Loan Fund and from the Norwegian State Housing Bank. Data are compiled for persons and households. The most important variable for the Census 2001 is After-tax income.
Data is primarily retrieved from the Register of Vehicles and the Driving licence Register. Data is also retrieved from the Register of Wage Sums about persons who have a car available for their use through their work.
Information on addresses of residents, dwellings, work places and schools/educational institutions is retrieved from the address section of the GAB- register. This is information on the basic statistical unit, municipality, etc., to which the address belongs and whether the address is located in a densely or sparsely populated area.
The housing forms were sent by mail to the oldest person in every family (contact person)2. Name and address were retrieved from the CPR and pre-printed on the forms. The contact person was to confirm whether the pre-printed address was the same as the address where they lived on 3rd November 2001. Further, there were several questions about the dwelling. The form also contained a list of names of persons registered as belonging to the same family. The contact person was to tick which of these persons who actually lived in the dwelling and supplement the list with any other persons living there.
The contact person was to return the form in an enclosed stamped addressed envelope or respond via Internet. Up to two reminders were sent to those who had not returned the census forms in time.
In addition information on place of usual residence was collected for students and pupils aged 16 and older. In principle every person who, during spring and autumn of 2001, applied for a grant from The State Education Loan Fund (Statens lånekasse for utdanning) received a student form. If the student was living away from home, the form was to be completed for the usual residence of the student.
It is estimated that the average time used to complete the housing questionnaire is 15 minutes. This amounts to approximately 70 000 man-days.
Register data used in statistics are verified and edited to a greater or lesser degree. Variables that are not found in any of the administrative sources are created by combining data from various register sources.
The questionnaires were scanned, and marked entries were read optically. Figures that were written in clear text (among others the number of different types of rooms) were scanned and processed by computer. Personal identity numbers of persons registered as residents in the household were found in the CPR. New addresses from the forms were checked so as to verify the CPR addresses. Statistics Norway did not contact respondents if forms were found to contain errors or were inadequately filled in. The data has however undergone some correction and verification by computer. Values were imputed for unanswered questions (item non-response) and forms that were not returned or returned in non-completed form (unit non-response). (See paragraph 5).
So far the results of Census 2001 have been published in two main ways. Main figures are regular tables in Today's Statistics, while more detailed figures are available in Statbank Norway. The statistics shall not provide information that can be traced back to individual persons. In respect of the protection of privacy, many of the tables have been adjusted in order that combinations of variable figures that only occur once or twice should not be identifiable in the tables.
In the regular tables, the figures 1 and 2 are relatively seldom. In instances where these values have to be suppressed, this is done by help of the standard sign ":" which indicates that the figure is "not for publication".
StatbBank Norway contains more detailed figures, which is why another method has been chosen to enable the protection of privacy. In most of the table matrixes at the most detailed level in every region (county, municipality, urban district), all figures 1 and 2 are replaced by 0 or 3 (the table matrixes affected by this will have foot notes when the tables are retrieved). The figures 0 and 3 also occur naturally, and it should not be possible to see the difference between the two types of 0 and 3. The replacements are done such that they do not influence figures retrieved at a higher level of aggregation. Nonetheless, small deviations from the original figures do occur. These deviations will generally be less than errors caused by the sources of error discussed in paragraphs 5.1 - 5.3, and will not reduce the utilitarian value of the statistics. When the same table is produced on the basis of two different matrixes, minor deviations may also occur between the tables.
The census comprises all persons considered resident in Norway (according to the CPR) on 3rd November 2001. The Population Registration Act of 16th January 1970 (with later amendments) and its provisions from 1994, define persons that are considered resident in Norway and where their address is to be. The total number of persons resident in a region is the population.
Two persons are considered a couple when they belong to the same household and are married to each other, are registered partners or cohabitants i.e., are living together without being married or without registering a partnership. To be considered cohabitants the couple must belong to the same household, and in addition have children in common or respond in the questionnaire that they are cohabiting. Married couples that are separated but registered as resident in the same dwelling are not considered cohabitants even when they have children in common.
A family consists of persons resident in the same dwelling and related to each other as spouse, registered partner, cohabitant, and/or parent and children (regardless of the child's age). At most, a family may consist of two subsequent generations and one couple only. This means that persons that are married or cohabiting and/or have their own children, do not belong to their parents' family. Persons who no longer belong to their parents' family because they are married and/or have their own children will not ever be added to their parents' family again. For example when a married couple live together with their divorced son/daughter, they are considered as two families.
Single persons are also considered a family such that all persons comprise a family, either together with others or alone.
Please note that this definition is slightly different from the one that is used in the current statistics on families, because the basis for the data in the latter makes it impossible to identify cohabitants if they do not have children in common. These persons are therefore not considered as belonging to the same family.
A household consists of persons that are permanently resident in the same dwelling (housing unit) or institution. Such a household is called a dwelling household. Census 2001 does not supply any information about housekeeping units i.e. persons living in the same dwelling with joint board.
A private household comprises persons resident in the same dwelling, where this dwelling is not an institution. An institutional household comprises persons who have board, lodging, care and nursing at an institution. Employees that are resident in an institution are always considered resident in a private household. Census 2001 does not provide any statistics for institutional households, however the number of persons not living in private households are given. This group is referred to as resident in other households and comprises persons resident in institutional households as well as persons of no fixed address.
In Census 2001, most statistics that are produced are based on legal residence (i.e. address according to the Central Population Register). However, information is also gathered on place of usual residence for students not living at home and for persons who live at old people's homes and nursing homes (corresponding information has not been gathered for persons living in other kinds of institutions).
The composition of households according to legal address is based on information given in the housing form and information on addresses retrieved from the CPR. Households may comprise one or more families. Persons belonging to the same family also belong to the same household. If persons who do not belong to the same family are to be considered a household, they have to be registered at the same CPR address and they need to have confirmed in the questionnaire that they live together. This means that unmarried students usually living away from home but registered at their parents' address are considered part of their parents' household. Only persons that are registered as resident at an institution are considered as belonging to a collective household. Many persons who live in institutions, for e.g., old people's homes and nursing homes, are registered as resident in a private dwelling (together with their spouse).
In composing households by place of usual residence, the place of study/institution address is used for these persons. This means that students are considered belonging to a household at the place of study (alone or with others according to the answer given in the questionnaire). For more information on usual address for students, see paragraph 4.2. Everyone permanently residing at an old people's home or nursing home is counted in institutional households, regardless of whether they have a spouse residing in a private household or not.
A dwelling is defined as one or more rooms that has been built or rebuilt for the purpose of being used as a round-the-year dwelling for one or more persons. It must be possible to have access to the room/rooms without having to go through another dwelling. Therefore, a dwelling is for e.g. a detached house, row house, an apartment in a twin house or block of flats, or a flat or bed-sitter.
A one-room flat in a private house is considered a dwelling as long as it has independent access. In a dwelling with bed-sitters every bed-sitter is considered a separate dwelling even though the kitchen and bathroom may be shared. Apartments and bed-sitters that are used by private households in hospitals, institutions, military quarters etc., are always considered independent dwellings.
Because the concept dwelling household is used, the number of dwellings is equivalent to the number of private households in the census. Most of the tables are of households by legal address. Here, information has only been gathered for dwellings where at least one person is registered resident. For tables on households by place of usual residence, dwellings inhabited by students have also been included even though there were no persons registered as residents of these dwellings.
Building is not a separate unit in the collection of data or the statistics however the statistics include some variables that apply to the building in which the dwelling is located. Building is in this context defined as a permanent detached construction with one or more dwellings. A building must have a roof and enclosing walls.
Persons are grouped according to age on 31st December 2001.
This variable shows the status of persons: whether they are married, a registered partner, cohabiting or single. In the tables, married and registered partners are classified together.
This is the address where the individual was registered as resident on 3rd November 2001. The main rule in population registration is that persons are to be registered as resident at the address where they spend the majority of their daily night-rest. There are however some exceptions, the most important being that unmarried pupils and students are to be registered where they lived before moving to their place of study3. Moreover, married persons living at old people's homes and nursing homes are normally registered together with their spouse if he/she lives in a private dwelling. Married persons and persons sharing a household with their own children, are to be registered together with their spouse and/or children even though they might be weekly commuters, for e.g.
Some persons cannot be connected to a specific address. These might be persons living in a boat or caravan, living temporarily with friends and family or with no place to live. These persons are considered resident in the municipality where they had their last permanent address. In statistics by statistical units, statistical tracts and urban settlements, these persons are registered in the group unknown.
During Census 2001, information was gathered on usual address at the place of study for students living away from home and institutional addresses for persons actually living at old people's homes and nursing homes. Similar information was not gathered for persons living at other institutions. For all other persons than those belonging to the aforementioned groups, usual address is the same as legal address. See also, Students - usual address.
The aim of the housing census was to collect information on usual address and housing for every student and secondary school pupil aged 16 or above, presumed to be living away from their parents. Every person who had applied for a grant from the State Education Loan Fund (Statens lånekasse for utdanning) during the spring or autumn of 2001, received a student form. This applied to 139 261 persons. Not every person who had applied for a grant was registered as a student or pupil in Norway on census day (3rd November 2001). This reduced the number to 103 886. Among these, 82 724 persons lived away from their parents. The census has information on dwellings for 78 771 of those who lived away from their parents. We do not have dwelling information for 3 953 pupils/students who did not return the forms. In statistics based on the student's usual address, these persons are included in the municipality of study.
A distinction is made between persons with or without immigrant background. The following categories are used for persons of immigrant background.
First-generation immigrants without a Norwegian background are persons born abroad with two foreign-born parents. These are persons who immigrated to Norway at a specific point in time. Persons born in Norway with two foreign-born parents are themselves born in Norway, but both parents and all four grandparents are born abroad.
This group comprises first-generation immigrants without Norwegian background and persons born in Norway with two foreign-born parents. This group is named the immigrant population and forms the basis of the statistics being published here.
This variable refers to the country where one is born i.e., mother's country of residence at the time of birth.
For persons born abroad, country background (national background) refers to their own country of birth. For persons born in Norway, this is their parents' country of birth. If their mother and father's country of birth is not the same, the mother's country of birth is chosen. For persons of non-immigrant background, Norway is always their country background.
Persons of immigrant background are categorised by country background. Western countries refers to Scandinavia, Western Europe (excluding Turkey), North America and Oceania. Non-western countries refer to Eastern Europe, Asia, Africa, South and Central America and Turkey.
Information on highest completed education is given for all residents that are 16 years old or above as well as for 15-year olds who have completed compulsory school or are taking further education beyond compulsory school. Information on education refers to 1 October 2001. For persons with several completed educations, only the highest level is given.
Type of education is based on the Norwegian standard for the classification of education (NUS2000) and is a 6-digit code giving level, field of study, subject group, educational group and individual educational programme. The tables in Census 2001 mainly use the two first digits: level and field of study.
The standard contains 8 levels. These are again grouped into four: below upper secondary education, upper secondary education, tertiary education, short (higher education 4 years ore shorter) and, tertiary education, long (more than 4 years).
This variable gives the least detailed classification of the academic content of the educational activities. There are 9 codes (and unknown in addition). See Norwegian Standard for Classification of Education. Revised 2000 (NOS C617).
A so-called re-coded version is used in Census 2001, i.e., the previous seven-year primary school is placed at the same level as the current compulsory school education. There is also a non re-coded version that can be used for special assignments.
This variable shows which persons are in education and comprises all pupils/students who have completed compulsory school. The information refers to 01.10.2001.
This group comprises pupils at folk high schools and in upper secondary education. Persons on labour market courses are also included. Upper secondary education comprises pupils participating in education of at least 300 periods (teaching hours) per year, irrespective of whether the education is officially approved or receiving public funds. Apprentices are in Census 2001 not included in the group pupils.
This group comprises persons in higher education, i.e., students at colleges and universities approved by the Ministry of Education and Research.
Complete data is available on pupils and students registered at educational institutions in Norway. Furthermore, there is information on students studying abroad and their country of study. In ordinary publishing, only pupils and students in Norway are included.
In classifying type of school, the grouping of educational institutions established by the 1994 Standard Industrial Classification is used. The following classification is used:
This variable gives the municipality location for the school/institution of education for pupils and students. For military schools, municipality of the school is not given.
Census week is 29th October - 4th November 2001.
In Statistics Norway's Labour Force Survey (LFS), employed persons are defined4 as persons that performed work for pay or profit for at least one hour in the survey week, or who were temporarily absent from work because of sickness, holidays, paid leave etc. Conscripts are also classified as employed persons. Persons engaged by government measures to promote employment are also included if they receive wages paid from an employer.
In Census 2001 and in other register-based statistics, the objective is to use available data to produce a classification of employed persons that is as close as possible to this definition. The most important register for identifying employed persons is the Register of Employees, which holds information on duration of jobs and thus shows what jobs that were active during census week. The other main data sources, Register of Wage Sums and The Register for Personal Tax Payers, do not have information on duration of jobs. In these cases, information on wages and income from self-employment as well as supplementary information from other registers and statistical systems is used to classify persons as employed. This method gives a figure of employed persons total that agrees with the corresponding figure from LFS. Since the LFS comprises the age group of 16-74 years, only persons in this age group may be classified as employed.
For employed persons with several jobs in the reference week, one is selected as the main job. Information on place of work (establishment), working hours and status in employment also refers to the main job.
This variable distinguishes between salaried employees and self-employed and refers to the main job. Salaried employees also comprise joint-owners of limited companies. Self-employed are persons running a business establishment on their own account (alone or with others).
In Census 90 and LFS, a third group is also distinguished: family workers (family members with no fixed-salary in a family-owned enterprise). It is not possible to identify this group in register-based statistics.
For salaried employees, this refers to settled weekly working hours in the main job, i.e., the number of working hours per week determined by the employment contract. For self-employed persons, usual working hours is estimated on the basis of available register information.
Industry describes the type of production or activity at the work place (establishment). Industry is coded by the 1994 Standard Industrial Classification (NACE), see NOS C182.
This variable is based on the Institutional Sector Classification, which is a statistical standard based on international guidelines of the System of National Accounts given by the UN (SNA 93), see NOS C614. In the statistics, enterprises/legal units are grouped primarily by socio-economic function, but also by organisational form and ownership. In Census 2001 the following main groups are used: central government, local government, counties, local government, municipalities, and private sector and government enterprises. The latter group comprises financial and non-financial corporations, households, non-profit institutions serving households and employed persons with sector unspecified.
The size of the establishment is measured by the number of persons employed in the establishment in census week. All employees are counted, including those who have their main job in another establishment.
This variable shows the address of the establishment where the employed person works (main job). Most establishments have a precise location and it is therefore possible in principle, to give figures for small regions such as basic statistical units. The quality of data for distributing workplaces into small regions is uncertain. In Census 2001, publishing of workplaces is therefore at municipal/ urban district level.
This variable specifies the municipality in which the establishment is located and follows from the location of the establishment. For employed persons for whom there is no information about municipality of work, or where the data available gives no information about the individual's workplace, municipality of residence is registered for municipality of work. This mainly applies to seamen and persons employed in military service, conscripts and some self-employed persons.
In Census 2001, information was not gathered on work journeys; however, statistics comparing place of residence and place of work is produced. In the statistics, legal address of residence is used.
By comparing the individual's place of residence with place of work, the scope of work journeys or commuting between regions is deduced. The statistics is published at municipal level. For some persons, the location of the establishment may not be the same as the place of reporting for work. Commuting is not necessarily the same as daily work journeys. Some people might be weekly commuters, others might be part time employees and some are working wholly or partly at home.
In-commuters to a municipality refer to persons who have their place of work in the municipality but are resident in another municipality. Out-commuters refer to persons living in the municipality but with their place of work in another municipality.
Census year is 1 January to 31 December 2001.
In Census 2001, as in the annual labour market statistics, employment is primarily describes by current activity, i.e. the situation in a short reference period (week). To facilitate comparing with previous censuses, statistics is also produced on employment during the year (usual activity). In Census 1990 employed persons in the year was defined as persons performing work for pay or profit for at least 100 hours during the year. All jobs, not only the main job, were counted. Sick leaves, holidays, paid leave etc was included in the working hours.
In Census 2001 the objective is to use available data to produce a classification of employed persons in the year that is as close as possible to this definition. Using information on wage sums, duration of jobs and weekly working hours, working hours per year is computed for all jobs. For self-employed persons information on income and information on working hours from the LFS is used. Total working hours is then the sum for all jobs, however some adjustments are made for the number of jobs allowed at the same time for each person. Working hour per years is computed for the age group of 16-74 years only.
Persons employed 100 hours ore more per year are classified by using total working hours per year. For employed persons with several jobs during the year, one is selected as the main job. This is the job with the highest number of working hours. Information on place of work (establishment) and status in employment refers to the main job.
Working hours per year is computed as described above. The precision in the computations is limited by the quality of input data. Therefore working hours per year is only given for intervals: 100-499 hours, 500-999 hours, 1000-1299 hours and 1300 hours or more. These intervals are the same as in the 1980 Census.
The other characteristics given are similar to the ones published for the census week. The difference is that they are related to the main job in the year. The characteristics are Status in employment, Industry, Sector, Number of employed persons in the establishment and Place of work. These are describes in Characteristics of persons - employment in census week
Couples are characterised by actual marital status (married or cohabiting) and the number of children. Please note that only children under 18 years belonging to the family of at least one of the parents are included. (See Number of children in the family).
All persons under the age of 18 that are registered resident in the family of at least one of their parents are considered children. Persons that are married or cohabiting and/or have their own children do not belong to their parents' family unit.
In the section about the unit household (point 4.1) persons that are to be considered as belonging to the same household are defined. Type of household is defined according to the Standard of Classification of Families and Households. A distinction is made between one-family households and Households with two ore more-families. A distinction is also made between households with and without children. For the definition of child, see Number of children in the household.
One-family households are grouped as follows:
Two ore more-family households are grouped as follows:
This variable is also named size of household.
Persons under the age of 18 who are registered as resident in the family of at least one parent are considered children. Persons who are married, cohabiting and/or have own children do not belong to their parents' family unit. Persons under the age of 18 who are registered as resident with other adults than their parents, for example foster children, are in this context not considered as children in the household.
This variable describes the household by the age of the oldest person in the household.
This variable describes the household by the age of the youngest child in the household. For the definition of child, please see Number of children in the household.
This variable denotes the number of cars available for the use of the members of the household. For each individual the basis of calculation is the number of cars owned by (registered in the name of) the individual person. Persons who have a company car available for their use are considered as having one additional car. The number of cars is summed up for all persons in the household.
Note that in Census 2001, this variable is register based, whereas in Census 1990, it was based on information from questionnaires. The figures are therefore not directly comparable, see point 6.1.
This variable refers to the type of tenure status the household has with regard to the dwelling. Both owner-occupiers and owners through housing co-operative or limited companies are considered owners. Ownership of bonds in a bonds company is considered as renting of the dwelling. For households renting dwellings, type of tenure status is given (from private person, housing company, the municipality, government/company housing, etc.).
The household owns the dwelling if at least one member of the household is registered as owner of the dwelling.
The data refer to the year 2001.
After-tax income is the sum of earned income (wages, salaries and net entrepreneurial income), property income and transfers (taxable and tax-free transfers), less assessed taxes and negative transfers. Data is first compiled for every member of the household and then aggregated to the total income for the household.
This variable refers to the number of persons registered resident in the dwelling on census day. Legal address is the basis for counting the number of occupants per dwelling/ household unless otherwise stated. The number of occupants in the dwelling is the same as the number of persons in the household.
Note that according to this definition, the number of occupants in a region only comprises persons living in private dwellings/households. This figure is slightly lower than the total population in the region, which also comprises persons not living in private households (institutional households, etc.)
Utility floor space is a standard of measure referring to the area within the enclosing walls of the dwelling. All types of rooms (also storage rooms) are included. Area consisting of a bed-sitter or flatlet that is rented out, rooms that can only be accessed by going out of the dwelling and lofts that are accessed by ladder are not included. Utility floor space is not directly comparable with useful floor space, which has been used in previous censuses, see paragraph 6.1
Number of rooms refers to living rooms of 6 square meters or more that can be used all year round. Kitchen, bathroom, WC, utility room, corridors and such are not included. Rooms that are only used for business purposes are not included either.
The kitchen is the part of the dwelling where cooking equipment is installed. The kitchen could be a separate room, however open kitchens are also considered kitchens. If several dwellings have a joint kitchen, for e.g. bed-sitters in a building of flatlets, all the dwellings are considered as being without a kitchen. There is information on whether such dwellings have access to a joint kitchen.
Bathroom refers to rooms where a bathtub and/or shower is installed
This variable refers to the number of water closets that are actually within the dwelling. Water closets outside the dwelling shared by several dwellings are not included.
For a wheelchair user to be able to enter the dwelling without help, certain requirements should be met. Among others, there should not be stairs hindering entrance into the dwelling and the front door should be at least 80 cm wide.
This variable shows whether a wheelchair user can use the bathroom, toilet, at least one bedroom, kitchen and living room in the dwelling without help. This is assessed irrespective of whether the person concerned needs help to get into the dwelling, or whether he/she can enter without help.
This variable gives the type of heater or systems for heating that exist in the dwelling, irrespective of whether of these are actually in use. In the statistics, dwellings are also classified by combinations of heating systems.
This variable refers to the sources of heating that are used to heat the dwelling.
This variable shows whether the dwelling has its own garage/carport and/or parking space. If occupants rent a garage/carport/parking space that does not belong to the dwelling, it is not included.
This variable gives information on whether the dwelling has access to its own garden or has a joint garden with neighbours.
This variable gives information on whether the dwelling has a balcony, veranda or terrace.
This variable shows the type of building in which the dwelling is located. The following categories are used:
Small houses is a joint term referring to groups 2 and 3 above.
This source for this variable is the GAB-register, and it is therefore not directly comparable with the corresponding variables from Census 90 in which information was gathered from questionnaires, see 6.1
Year of construction is the year the building was ready to be occupied. In buildings with several dwellings where occupation was gradual, year of construction is the year in which at least half of the dwellings in the building were ready to be occupied. For reconstructed houses, the original year of construction is given.
This variable gives the total number of floors in the building in which the dwelling is located, irrespective of the floor where the dwelling is located. Basement or lower ground floor is not included even if it is wholly or partially furnished for living. Loft is only included if it is furnished for living.
This variable provides information on whether a lift has been installed in the building. Lift here means passenger lift, not hoist or stairway elevator installed in a detached house.
Region is a level between counties and the whole country. The regions consist of a whole number of counties. Norway is divided into 7 regions: Oslo and Akershus, Hedmark and Oppland, South Eastern Norway, Agder and Rogaland, Western Norway, Trøndelag and Northern Norway. The first three mentioned here are also referred to as Eastern Norway.
The county distribution as at 1 January 2002 is used.
The division into economic regions is a regional division between the county and municipal level. This division supersedes Statistics Norway's grouping of trade districts and forecast regions. The country is divided into 89 economic regions. The name economic region is used because the criteria for demarcating regions are related to the region's economic conditions (labour market, retail trade). For more information, see Standard for Economic Regions (NOS C616). The grouping used in Census 2001 has been revised in accordance with the county-municipal division as at 1 January 2002.
The municipality distribution as at 1 January 2002 is used. Våle and Ramnes municipalities of Vestfold were joined on 1 January 2002, and named Re municipality. Ølen municipality was moved from Hordaland county to the county of Rogaland.
Urban districts constitute geographic areas in an urban municipality. Administrative and political urban districts are geographic areas with a local administration, separate administration and political government. In official Norwegian statistics, the term urban district is related to the four largest urban municipalities: Oslo, Bergen, Trondheim and Stavanger. The urban districts are made up of whole basic units, but not always of whole statistical tracts.
Statistical tract is an intermediate level between municipalities and basic units. A statistical tract is a collection of a whole number of basic units, and a municipality constitutes a whole number of statistical tracts. There are approximately 1550 statistical tracts.
The purpose of dividing municipalities into basic units is to organise small and stable geographic units that are suitable for the presentation of regional statistics. Basic units are organised so as to be stable over a reasonable time period and are to constitute a contiguous geographic area. Their demarcation is not connected to the demarcation of urban settlements. A basic unit may therefore contain both dense and sparse populated areas. Basic units are not required to coincide with parish, school or constituency boundaries. There are approximately 13 700 basic units.
Centrality is a measure of a municipality's geographical position seen in relation to a centre where a higher order of functions (central functions) is found. Central functions are found mainly in urban settlements. Urban settlements are divided into three levels according to size of population. Municipalities are divided into seven groups of centrality; see Standard Classification of Municipalities 1994 (NOS C192). In the tables the following classification is used:
The uncertainty of figures is due to several factors. Sources of error may be sorted into five main groups: errors of non-response, measurement errors, processing errors, register errors and model errors. We will describe how these errors influence the total uncertainty of the figures.
We have to expect some response errors in the housing form. This might be because the respondent misunderstands the question, for instance what should be counted as a living room. Some questions might be difficult to answer precisely, for instance the exact size of the dwelling in square meters. Generally, it may be expected that questions requiring less time to fill out have a better quality than questions requiring more time, particularly if one needs careful consideration before responding.
We must also envisage processing errors in the optical reading of the forms. A typical error that can occur is for e.g., one reads the number 7 as 1 and vice versa. Ticked entries that are faint or placed outside the box they were to be printed into; might be interpreted as non-response. Many, but not all, wrong interpretations are corrected during revision.
We have a comprehensive system for finding and correcting data errors (see also paragraph 3.6). The actual measurement error in the data we use to produce statistics is thus the deviation between the true (but unknown) value and the actual value in data. This actual value then is a result of the given response, its interpretation and the errors we corrected through our control and revision routines. The level of measurement errors might be assessed by comparison with data from sample surveys. Separate notes on measurement errors will be published in 2003.
One way of describing measurement errors is to distinguishing between systematic errors (average measurement error) and random errors (individual measurement error). In small areas (municipalities and urban districts), the latter will be of most importance i.e., differences between municipalities may be due to random deviations. For larger regions, such as the whole country or counties, the systematic error will be most important i.e.; the figure of a certain variable might remain too high or too low compared to the true value.
In Census 2001, register data is the same as that which is used in various sector statistics published by Statistics Norway. For descriptions of quality, we refer to About the statistics for individual sector statistics.
Sample errors are not topical in Census 2001 because it was a total count. However sample errors are significant when we need to explain deviations between the final figures and the preliminary figures that were published in April 2002. The preliminary figures were based on a sample of the incoming forms and were therefore subject to sample errors. Deviations between the preliminary figures and the final figures are also caused by non-response errors and processing/measurement errors. In most cases, the differences are clearly within the expected deviation.
Non-sample errors may be sorted into register errors, non-response errors and model errors. Non-response is more likely to affect the quality of the figures being published than the two other error sources. Non-response errors could also be an indirect result of register errors. Addresses from the Central Population Register were used when the forms were issued. However, it turns out that almost 40 000 forms were returned from The Post Services. This must be largely due to the fact that the contact persons were not reached at their CPR address. There might be several reasons for this: for e.g., 30 000 persons do not stay at their permanent address or they may have moved without sending notice of change of address to the CPR.
Model errors are also related to non-response errors. The routine for imputing information for non-response is based on models for the correlation between values for units of non-response and corresponding values for units whose forms were received.
We will put more emphasis on describing the uncertainty that arises when we have to impute values where information is lacking. Non-response may be divided into two groups. Firstly, we lack information for 138 500 housing forms (i.e. households) that were issued. The two predominant groups among these are 93 300 forms that were never returned even after the second reminder was sent, and 40 000 forms that were returned form the Post Services. In some cases the contact person/family was exempted. Some forms are so poorly filled in that they cannot be used at all. When the form is missing or completely useless, it is referred to as unit non-response.
The second type of non-response occurs when certain questions are not answered at all or we are unable to interpret the answers. This type is called item non-response. The extent of this type of non-response differs from question to question. These discrepancies are probably related to the degree of difficulty that the respondent has when answering the question. In other cases it might be because the respondent do not want to give the information asked for. Item non-response is much higher in the paper forms than on Internet. This is because on the Internet we were able to put in reminders for the respondent when questions were not answered.
The routine for imputing housing information for the households from which we did not receive a form is based on the following: For every non-response household a dwelling is randomly selected in the same basic (geographical) unit. The selected dwelling is located in the same type of building (detached house, twin house, block of flats etc) and the household living there is of the same type (couple/no couple and number of children). The dwelling information of the dwelling selected becomes that household's estimated dwelling information. Moreover, there was stratification according to whether the family was non-western immigrant or not. We see that non-response is much higher when there is no couple in the household and clearly higher for households living in multi-dwelling buildings.
We can sum up by establishing the fact that non-response does not cause errors in the figures for married couples, registered partners or cohabitants with children in common. However we should reckon that we have too many persons who are either living alone or are mother/father with children since some of these persons should probably have been combined into larger households of "cohabitants without children in common". This also implies that the number of cohabitants is too small. The size of these errors is probably minimal and is of no significance for the interpretation of figures and comparability with other statistics.
As regards labour market statistics, Census 2001 uses a newly developed basis of data that has not been previously used in publishing official statistics. A short description is therefore included here. Furthermore, quality measures for register statistics were also developed as a part of the Census project. The main principle is to compare register data with data from sample surveys. The results will be published in 2003.
In order to determine which persons should be classified as employed persons in the reference week, data from several registers is used (see 3.4). For persons defined as employed persons solely on the basis of information from the wages, tax and deductions statement (about 10 percent of wage earners), the employment is not dated. Information for about half of this group is retrieved from other administrative sources, which help to date the employment. For the remainder of the group, information on wages is used to determine whether a person is to be considered employed. There is therefore a certain uncertainty as to whether the employment was actually active during census week.
Self-employed persons are identified by using information from the tax return register. Due to long production time, information about industry from the previous year is used to compile the statistics. As a result of this delay, persons may have been wrongly classified as employed if they terminated their employment activity in the previous year.
For persons defined as employed and wage earners, solely on the basis of information from the wages, taxes and deductions statement, employment is linked to an establishment. Here, a routine has been established in order to identify the establishment in the best possible way. In cases where a person is employed in a multiple business establishment, it is sometimes uncertain whether the employment is connected to the right establishment and whether correct information is deduced about industry, workplace and size of the establishment
A more precise description of the scope of errors will be published in a separate quality survey. It may be generally stated that for persons in stable employment in 2001, for e.g., employment that lasted throughout the year, the quality of the employment information is very good. For persons with a more unstable employment, the quality of the employment information is not as good. We must also expect that the quality of employment information is poorer for the youngest and oldest than for the age group between 25 and 55 years.
In Census 2001 information is given on pupils/students who are also employed. The proportion is particularly high for students (75.5 percent), compared to other surveys. There may be several reasons for this.
All those registered at a college or university are considered students. For the universities in Oslo, Bergen, Trondheim and Tromsø, all those who paid the semester fee are included, however some of these persons are not active students. In other cases, the employment is an integrated part of the education itself. This applies to apprentices for e.g., and this group is therefore not included in the statistics. However, it also applies to other groups such as persons being educated at state schools. Thus the group pupils/students does not only comprise those who have education as their most important activity or those who study full time, but also includes for e.g., persons taking supplementary education related to their employment.
Dating of some employment conditions is uncertain (see Employment above). This particularly applies to persons in temporary employment and/or part time workers. Pupils/students often have this type of working condition. There is therefore a certain degree of uncertainty involved as regards the time of year when pupils and students are employed. For e.g., a possible error is for some students with summer jobs to be classified as employed during census week in October/November.
The quality of commuting figures depends both on information about the location of address and the location of the workplace. Legal address is used. For the majority, this is equivalent to usual address. However there are deviations, particularly with regard to students. Students living away from home will often be registered as resident at their parents' home address. If they have a job at their place of study, they will be considered as commuters. Consequently, the proportion commuting is slightly exaggerated, particularly for the youngest age groups.
The workplace location is the address of the establishment, which is not always the same as the individual's actual agreed workplace. Employed persons without a permanent workplace are registered with the workplace municipality to which they belong for administrative purposes. This particularly applies to persons working in the construction and transport industry. Further, due to weaknesses in the basis of data, certain employed persons are only connected to the head office address (see under Employment). In summary, commuting towards the larger cities and regional centres in the statistics is slightly overestimated as a result of these factors.
For persons for whom information on workplace is lacking, municipality of residence is registered for workplace municipality. This mainly applies to persons employed in Defence, military and non-military national servicemen, some self-employed persons as well as seamen. As a result, there may be some underestimation of commuting for these groups.
An important objective of Population and housing censuses is to be able to follow the development over time. As regards comparability with previous censuses, the main emphasis is put on comparability with the previous census (Census 90).
Generally, changes from Census 90 to Census 2001 consist in the fact that new variables have been created. In Census 2001, education is coded from the last edition of the Norwegian Standard for the Classification of Education (NUS 2000 based on ISCED97). In Census 90 the previous edition of this standard was used (NUS89).
In Census 90, labour market data was collected by using questionnaires, while register data is used in Census 2001. Even though the definitions used are the same, this change in the method of data collecting might still cause some changes in the statistics. Some particular factors are discussed below.
In Census 90 only persons who stated that they were employed in the census year were to respond to questions on employment during census week. Variables such as occupation and industry, etc., were then related to the main employment that year. In Census 2001, employment in the census week is determined irrespective of whether the person was employed at least 100 hours that year or not. In Census 90 the term economically active was used for what is referred to in Census 2001 as employed persons.
The register of employees has a classification of three intervals for settled working hours per week for employees. For other groups of employed persons, usual working hours is estimated (for the same intervals) on the basis of wages, income and duration of jobs (when known). In Census 90, questions were asked about usual/settled weekly working hours grouped into six intervals of time. According to the guidelines, settled working hours were to be stated if a contract existed. With regard to the variable settled/usual weekly working hours, there is therefore good consistency between Census 90 and Census 2001. Furthermore, in Census 90 the question was asked about hours actually worked per week. This variable is not included in Census 2001.
In Census 2001, industry is coded from the last edition of the Standard for Industrial Classification (SN94) also referred to as NACE (based on the UN's standard, ISIC, 3rd edition). In Census 90, the previous version of the standard was used (based on the UN's standard, ISIC, 2nd edition).
For Census 2001, an attempt was made to deduce occupation by use of register data. However the data quality for the year 2001 was not satisfactory so this variable is not included in Census 2001. However it is expected that the register-based labour market statistics for 2002 will include information on occupation.
In Census 90, a question was asked about place of reporting for work during census week. One alternative answer was no fixed place of work, and furthermore place of work was not stated by relatively many respondents. As a result, information on place of work was lacking for about 16 percent of persons employed during census week. In Census 2001 information on place of work is given for all employed persons. However this referred to the location of the establishment, which do not always correspond with the place of reporting for work for the individual person.
In Census 90, in addition to information on commuting, there are three variables related to journey to work: travelling time, number of journey per week and means of travel to work (means of transportation). Since there exists no register data for these variables, they are not included in Census 2001.
In Census 90 (and in previous censuses) the variable used was disposable income, but in Census 2001 after-tax income is used. These concepts are somewhat different. When calculating disposable income, interest payments are subtracted. This is not the case when calculating after-tax income. Furthermore, data on property income was less complete in 1990 compared to 2001. The result was that total household income in Census 90 was substantially underestimated.
Compared with Census 90, definitions of family in particular have been changed. In Census 90, each cohabitant was considered as comprising their own family; this also applied to cohabitants with children in common. This means that the number of families in Census 90 is higher than what it would be if the Census 2001 method had been used.
This also influences the classification of households, particularly the division into single-family and multiple-family households. Statistics Norway's Standard for Classification of Households and Families is from 2001. The classification of families and households in Census 90 slightly deviates from this one.
In Census 1990, information on this variable was gathered from questionnaires. In Census 2001, this variable is based on the registers. Information is retrieved, from the register of motor vehicles, about the number of private cars registered in the name of individuals in the household. In addition to private cars, smaller combi-cars and vans and mini buses are also included. The register of wage sums provides information on persons liable to tax charge on private use of company car.
The sources of data used in Census 2001 enables us to detect the majority, but not all households with cars available for their use. This is due to some households having a car available for their use, owned by (registered in the name of) a person belonging to other households. For example, some younger persons have cars available for their use that are registered in the name of one of their parents. Neither cars available for use through leasing nor cars used for organised car sharing are included. There is also reason to expect that some persons may use company cars to such an extent that they would respond in a questionnaire that they have a car available for their use, although this does not fall within regulations on additional tax charges.
As a result, figures from Census 2001 are not directly comparable with the Census 90 figures. A direct comparison shows a decrease in the percentage of households with a car available for their use. This is probably not real. The Survey of consumer expenditure shows an increase from 76 to 79 per cent for the period 1990 - 2000.
In Census 90 (and in previous censuses) useful floor space was used as a measurement of the size of the dwelling. Useful floor space was specified in the form as the area of all rooms used for living purposes. In Census 2001, utility floor space is used. Utility floor space was specified in the forms as the area of all types of rooms including storage rooms within the walls of the dwelling or flat. The difference between useful floor space in Census 90 and utility floor space in Census 2001 is that store rooms, utility rooms, boiler rooms, etc., were not included in Census 90. Thus the concept used in Census 2001 gives most dwellings a greater area than the concept used in Census 90.
In Census 2001, type of building is retrieved from the GAB-register. If type of building was unknown in the GAB register, this information was gathered from the housing form. The transition to using the GAB register as the main source complicates comparability with previous censuses because a change observed might be due to the transition to a new source of data rather than real changes over time. At national level, the figures show a strong increase in the number of dwellings in the group Commercial buildings, residential building for communities or similar from Census 90 to Census 2001 (about 70 000 dwellings). Part of this is because this group in 2001 includes about 15 000 bed sitters, for which type of building was unknown in the GAB-register. At least a part of the remaining increase is probably due to the transition to a new source of data.
The 1980 and 1990 housing censuses only provided figures for dwellings where persons were registered as resident according to the Central Population Register. In Census 2001 we also have collected information on dwellings of unmarried students who usually are living in another dwelling than where they are registered resident (i.e., dwellings considered "empty" by the Central Population Register).
Current family statistics is based on register data thereby providing no possibility of identifying cohabitants if they do not have children in common. These persons are each counted as individual families and are classified under "Other family type". In Census 2001 cohabitants without children in common are identified by data from the housing questionnaires. These persons are therefore considered a family provided they live in the same dwelling.
Annual household statistics are published as a part of the Income and property statistics for households and are based on data from a household survey. In this statistics households are defined according to usual address and not by legal address as in Census 2001 (see point 4.2). In the income statistics, unmarried students usually living away from home are considered belonging to a household at the place of study. In Census 2001 these students are considered part of their parents' household. As a consequence the per cent of households with adult children is higher in Census 2001 compared to the income statistics, while the per cent of households consisting of one-person households and couples without resident children is lower. Furthermore, in the income statistics households are defined on the basis of the housekeeping unit while the dwelling unit concept is used in Census 2001.
The housing census intersected with several sector statistics, the most important being the building statistics, the house price index and level of living surveys. In the building statistics and the GAB-register, utility floor space is the standard used to measure the size of dwellings. The housing census is to be used to upgrade the GAB-register with information on utility floor space of dwellings located in multiple-dwelling buildings. Furthermore, in future, housing censuses will be based on the GAB-register. Consequently in 2001, Statistics Norway chose to ask questions about utility floor space in the housing census. This deviates from the level of living surveys, which use useful floor space. There is therefore good comparability with the building statistics and other statistics based on information from the GAB-register. Comparability with future housing censuses will also be good.
The total number of employed persons in the register statistics is equivalent to that of the Labour Force Survey; see definition of employed persons under point 4.2. This also applies when employed persons are grouped into wage earners and self-employed. When grouped by other variables such as gender, age, industry, workplace and working hours, there will however be discrepancies due to the different data sources and methods used.
Statistics has been previously published on employees, respectively grouped into place of residence and place of work. The employee statistics is based on data from the employee register and comprises about 80 percent of all employed persons.
In the annual labour market statistics, there is no information on persons employed 100 hours or more per year.
The concept of after-tax income is used both in Census 2001 and in the annual income statistics. The difference between Census 2001 and the income statistics, for instance in respect to estimates of median income per household, is due to difference in the definition of households (see Households). Since the number of one-person households is lower in Census 2001, the median income for all households is somewhat higher than in the income statistics.
Final figures from the Population and Housing Census 2001 will be available at http://www.ssb.no/english/statbank/. Here, it is possible to define individual tables from a database. One is free to select variables one wishes to search for as well as the geographic area the data should cover.
Norwegian and English.
Figures from the Population and Housing census 2001 will also be published in paper in the series, Official Statistics of Norway. Furthermore this publication will be available on Internet in pdf-format http://www.ssb.no/fob_en/.
An overview of all variables available in Census 2001 will be published in a separate handbook for Census 2001 (in Norwegian and English).
1 This refers to the existing regulations for population registration as at 01.01.2001.
2 Two concepts of family are used in Census 2001. In the statistics published, family is defined as stated in 4.1 i.e. persons resident in the same dwelling and related to each other as spouse, registered partner, cohabitants and/ or parents and children. In the data collection register data was used, which means it was not possible to identify cohabitants who did not have children in common. In the data collection, these persons were therefore considered as two families.
3 Refers to the rules and regulations for population registration in force until 1 November 2001
4 This definition is based on the recommendations given by the International Labour Organisation (ILO) for producing labour market statistics.