Concepts and definitions


In connection with vital events, age data refer to the age on the day the event took place. Average age is obtained by adding up the ages of all persons involved in the same event at the time of the event, after which the sum is divided by the number of these persons. As the used age of a person is given in full years at the time of the event, it is not the exact age of that person. For this reason, it is assumed when computing average age that the persons were aged x+0.5, on average, at the time of the event.

Change of population

Change of population is defined as increase of population added up with register corrections.


Persons permanently resident in Finland on the day of their death are recorded in the statistics as deaths. Data on deaths are obtained from the Digital and Population Data Services Agency’s Population Information System. The number of deaths may differ somewhat from each other in different statistics. The difference is due to the different compilation times of the statistics. The official number of deaths in Finland is derived from the deaths in the population statistics.

Excess of births

The excess of births, that is, the natural population increase, refers to the

difference between livebirths and deaths.


Liveborn is the term for a newborn who breaths or shows other signs of life after birth. Only liveborn children of women living permanently in Finland are taken into account in the population statistics.


Starting from the statistical reference year 2017, contracted marriages refer to marriages where at least one of the spouses has resided permanently in Finland on the day when the marriage was contracted. The amendment to the Marriage Act that entered into force on 1 March 2017 enabled same-sex couples to enter into marriage (156/2015).

The number of marriages contracted annually is, thus, the number of marriages entered into by same-sex and opposite-sex spouses.

In 1980 to 2016, contracted marriages referred to marriages of women living permanently in Finland unless otherwise stated.

As a result of the amendment to the Marriage Act, starting from 1 June 2019, a person under 18 years of age shall not marry in Finland (351/ 2019).


The population refers to the permanent resident population of an area (e.g. entire country, province, municipality). Those persons who according to the Population Information System had a legal domicile in Finland on 31 December belong to the permanent resident population in the country regardless of their nationality, as do Finnish nationals residing temporarily abroad.

Foreign nationals are domiciled in Finland if their stay is intended to last or has lasted at least one year. An asylum-seeker is not granted a legal domicile until his/her application has been approved.

The staff of foreign embassies, trade missions and consulates, their family members and personal employees included, are not counted among the resident population unless they are Finnish citizens. On the other hand, the Finnish staff of Finland´s embassies and trade missions abroad and persons serving in the UN peacekeeping forces are counted among the resident population.


The resident population of Finland on 31 December is derived from the Population Information System maintained by the Population Register Centre. Since the data for 1993, Statistics Finland and the Population Register Centre have had the same reference period, the turn of the year at midnight, which means that the number of population has been the same.


The information about sex has been obtained from the Population Information System.

Total change

Total change is increase of population added up with register corrections of population. Increase of population is the sum of excess of births and total net migration.

Referencing instructions:

Official Statistics of Finland (OSF): Preliminary population statistics [e-publication].
ISSN=2243-3627. Helsinki: Statistics Finland [referred: 21.10.2021].
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