Population 1 December

0. Registration entry for subjects

0.1 Name

Population 1 December

0.2 Subject area


0.3 Responsible authority; office, division, person etc.

Ómar Harðarson
Guðjón Hauksson
Brynjólfur Sigurjónsson
Statistics Iceland

0.4 Purpose and history

From 1703 until 1960 the population was determined by a census. From 1960 onwards the population has been determined annually based on the National Register of Persons as it stands on 1 December. The register contains information on the delevopment of the population as well as its composition.

0.5 Users and application

Ministries, municipalities, institutions, companies, organisations and individuals.

0.6 Sources

The National Register of Persons, where information on deaths, births, migration, marriages, divorce, changes to nationality and adoption is recorded.

0.7 Legal basis for official statistics

Act on Statistics Iceland no. 24/1913. Act on the National Register of Persons and registration no. 54/1962.

0.8 Response burden

0.9 EEA and EU obligations

1. Contents

1.1 Description of content

From 1910 the census in Iceland has been taken on the 1. December, and since the founding of the National Register of Persons in 1952 the population has been measured on that day. From a demographic point of view the date itself, 1. December, has little significance and in its calculations the Population Department of Statistics Iceland above all relies on the mid-year population (1 July) and end of year population. However, the administrative value of the 1 December figures is still significant. The distribution of financing to municipalities still relies on the population on that day; it is therefore important that as accurate figures as possible are available by regions and municipalities. This has lead to that the by far most extensive tables from the Population Department on the composition of population by municipalities are based on figures from 1. December.

Information is collected on the total population domiciled in Iceland from the National Register of Persons on 1 December (according to Act no. 5 on domicile from 1990). The following appears in the published press release:

  • Population by sex, age and membership of religious organisations.
  • Population by constituency, streets, post codes, municipalities and regions.
  • Population in urban nuclei and rural areas.
  • Population development in Iceland over a ten-year period.

1.2 Statistical concepts

Preliminary statistics: Figures from the National Register of Persons as they stand on 1 December of each year. Differences between preliminary and final statistics mostly occur due to decisions on the domicile of individuals in ambiguous cases.

Urban nucleus: A town, village or other area where inhabitants live in houses standing in the vicinity of one another. The urban nucleus either has its own name, or is considered one in the area.

Localities: Classification by size of locality is the basis of dividing inhabitants by size class of locality, and distinguishing urban nuclei, less densely populated areas and rural areas. In 1960 Statistics Iceland sorted the population by whether living in urban nuclei or rural areas, according to harmonised definitions used in the Nordic countries, which are based on the United Nations framework. Itemisation by size class of locality is used, ie. by number of inhabitants of localities. The boundary between urban localities and rural areas was set at localities with 200 inhabitants or more when nothing else is specified. Previously the boundary was at 300 in accordance with the law on local authorities of 1905, according to which towns with at least 300 inhabitants could become separate municipalities.

A persons domicile is where they are ordinarily resident. One is considered to be ordinarily resident in the place where one usually spends free time, has ones property and sleeps when not temporarily away owing to leave, work related travel, illness or other similar reasons.

2. Time

2.1 Reference periods

The National Register of Persons is used as it stands at 1. December of every year.

2.2 Process time

The National Register of Persons is used as it stands at the end of the day 1 December and the press release is published the week before Christmas.

2.3 Punctuality

Population statistics are published according to the release plan.

2.4 Frequency of releases

Preliminary statistics for 1 December are published the week before Christmas; final Statistics are published during autumn of the following year.

3. Reliability and security

3.1 Accuracy and reliability

There are three sources of errors to numbers in the National Register of Persons: Late notifications of change of address, late death certificates and late birth reports. In a survey of delayed reports over the past 5 years it emerged that the greatest uncertainty was caused by late notifications of change of address, due to which on average 80 persons are under- or overestimated in the National Register of Persons on 1 December. Late death certificates cause the number of persons in the National Register of Persons to be overestimated on 1 December by around 10 persons, while late birth reports cause the number to be underestimated by one person every two years. The error to the total population in the National Register of Persons is thus, on average, around 90 persons plus or minus (an error of 0.03%).

Comparison of the census and the National Register of Persons is another way of evaluating errors in the register taken of the National Register of Persons on 1 December. Statistics Icelands last census was carried out 31 January 1981 and counted a total population of 227,870. However, the National Register of Persons for 1 December 1980, updated for 31 January 1981 showed 229,208 individuals. The population in the National Register of Persons was thus overestimated by 1,338 individuals (around 0.6% error). The year 1960 a census was taken, as well as a register from the National Register of Persons on 1 December. This year the National Register of Persons overestimated the population by about 1,612 persons according to the census (an error of around 0.9%).

It is likely that a large proportion of those who go abroad for a shorter or longer period of time, for education or work, choose to stay registered in the National Register of Persons either to retain rights within the social security system or simply due to apathy. It is therefore to be expected that a greater number of individuals is registered in the National Register of Persons on the 1 December than are in fact present in the country. It can also be expected that the number of inhabitants in certain municipalities is either over- or underestimated. In this respect it can be noted that individuals studying in Reykjavik often keep their domicile elsewhere.

3.2 Sources of errors

Errors in the National Register of Persons mainly occur due to delays in notification of change of address, delayed birth reports and death certificates. In order to keep errors to a minimum the National Register of Persons of 1 December is corrected 15 days back in time, ie. half a month is allowed to pass during which notifications of change of address, birth reports and death certificates are allowed to arrive.

3.3 Measures on confidence limits/accuracy

Confidence limits are not calculated.

4. Comparison

4.1 Comparison between periods

A register for 1 December was first taken from the National Register of Persons in 1960. The processing has been similar from year to year and statistics from early years are comparable with those of later years. In 1988 the National Register of Persons changed somewhat when ID numbers were introduced, though this change is not thought to have had any impact on the quality of figures in the National Register of Persons on 1 December.

4.2 Comparison with other statistics

4.3 Coherence between preliminary and final statistics

Differences between preliminary statistics and final statistics for 1. December are mainly due to decisions where there is ambiguity as to the domicile of individuals. Over the last four years the difference has never been over 25 persons between preliminary and final statistics. In 1998 the difference was 13, in 1999 it was 15, and 2000 it was four, while in 2001 it was 25.

5. Access to information

5.1 Forms of dissemination

  • Website of Statistics Iceland
  • Press releases of Statistics Iceland
  • Statistical Yearbook of Iceland
  • Statistical Series, the monthly publication of Statistics Iceland
  • Population statistics until 1980, in the series Hagskýrslur Íslands.
  • Hagskinna. Icelandic historical statistics.

5.2 Basic data; storage and usability

Data stored in digital format by the Population Statistics Department of Statistics Iceland. No access is provided to data relating to individuals, though it is possible to have it especially processed.

5.3 Reports

5.4 Other information

Further information is available from the Population Statistics Department of Statistics Iceland.

© Hagstofa �slands, �ann 27-1-2009