Background Notes

Coverage

The reference period for the population estimates is mid-April of each year. The migration flows are in respect of the twelve months to mid-April of the corresponding years, as are the births and deaths. The usually resident population classified by age and sex for 2016 are taken from the Census of Population.

Usual residence population concept

For the purpose of this release the population concept of usual residence has been used, i.e. all persons usually resident and present in the State on census night plus absent persons who are usually resident in Ireland but are temporarily away from home and outside the State on census night. All persons are classified according to their region of usual residence.

Migration Definitions

Immigration - means the action by which a person establishes his or her usual residence in the State for a period that is, or is expected to be, of at least 12 months, having previously been usually resident in another Member State or a third country.

Emigration - means the action by which a person, having previously been usually resident in the State, ceases to have his or her usual residence in the State for a period that is, or is expected to be, of at least 12 months.

Source of Migration data

The principal source of information for the estimation of the gross annual migration flows is the Irish Labour Force Survey (LFS), which also provides the basis for the classification of the flows by sex, age group, origin/destination and nationality.

The migration estimates are compiled with reference to movements in other migration indicators such as the number of Personal Public Service (PPS) numbers allocated to non-Irish nationals and new registrations with the Garda National Immigration Bureau (GNIB). The number of visas issued to Irish nationals to a number of destinations including Australia, USA and Canada are compared with the emigration data collected by the LFS. In addition, data on National Insurance numbers (equivalent to PPS numbers) issued to Irish nationals in the UK is referenced. Mirror statistics measuring the flows of Irish nationals to/from the EU28 are also examined.

The release also provides estimates of immigration and emigration by educational attainment (Table 5) and principal economic status (Table 6), based on responses in the LFS. The principal economic status question refers to persons aged 15 years or over and is a self-perception question, i.e. people are classified according to how they perceive their situation.

As with all breakdowns of migration (by age, nationality, origin and destination), the breakdown by educational attainment and principal economic status should be considered broadly indicative given the relatively small sample sizes associated with these flows. In addition, as a person's principal economic status can change over the course of a year (and to a lesser extent their educational attainment), for immigrants these two tables refer to their status in the quarter prior to the April of the year in question, while for emigrants it is their status in the period prior to departure.

Calculation of annual population estimates

The annual population estimates for mid-April are calculated by trending forwards the previous Census of Population data. For example, the base population data for estimating the April 2017 figure was the number of males and females in each region by single year of age and nationality as established by the 2016 Census. From this base, each person was aged by one year, births for the period were added and deaths were subtracted. The estimated number of immigrants was then added and the number of emigrants was subtracted. Allowance was also made for estimated inter-regional migration in arriving at the final 2017 figures.

The end result of this overall process provided the population estimate for April 2017 which in turn will provide the base population for the subsequent year and so on. The population estimates are subject to revision once the definitive results of the next census become available.

The population by nationality estimates are made possible by trending forwards the previous Census of Population and incorporating gross migration flows by nationality based on responses in the LFS. Allowance is also made for the non-Irish nationals who acquire citizenship certificates over the period in question. The number of births by nationality is estimated using the distribution of the nationality of births as recorded in the 2016 Census, while deaths by nationality are also estimated based on recent census results using the nationality distribution of the population by five year age groups.

Natural Increase

The General Registration Office (GRO) supplies registered data for births and deaths and these are typically added to the population file quarterly in arrears (N+1).

Internal migration

By examining a person's usual residence at the time of a census and one year previously it is possible to determine inter-regional migration patterns. Following each Census a new internal migration matrix is produced and used to measure inter-censal internal migration. Internal migration for the year to April 2018 takes account of the Census 2016 results.

Nationality

All persons with Irish nationality or citizenship are classified under the category "Irish" in table 9 (Estimated population classified by sex and nationality).

The Irish Naturalization and Immigration Service provide annual data for persons who acquire Irish citizenship. The availability of the citizenship data for year N is N+2 and so estimates for 2018 and subsequent years will be achieved by trending forward the rates noted for the most recent year available. Therefore, for the purpose of the 2018 release the 2016 distribution of citizenship acquisitions was applied.

Citizenship Certificates issued 2012 2013 2014 2015 2016 UK 85 55 51 54 98 Rest of EU 15 75 91 149 145 170 EU 13 1,265 1,615 2,725 2,921 3,058 Rest of World 23,685 22,482 18,177 10,443 6,712 Total 25,110 24,243 21,102 13,563 10,038

NUTS2 and NUTS3 Regions



The Nomenclature of Territorial Units for Statistics (NUTS) were created by Eurostat in order to define territorial units for the production of regional statistics across the European Union. In 2003 the NUTS classification was established within a legal framework (Regulation (EC) No 1059/2003).

As the administrative territorial breakdown of EU Member States is the basis of the NUTS classification, changes made under the 2014 Local Government Act prompted a revision to the Irish NUTS 2 and NUTS 3 Regions. These changes included the amalgamation of the local authorities of Tipperary North and South, Limerick City and County Councils and Waterford City and County Councils. In addition three Regional Assemblies were established (Northern & Western, Southern, Eastern & Midland).

The main changes at NUTS 3 level are the transfer of South Tipperary from the South-East into the Mid-West NUTS 3 region and the movement of Louth from the Border to the Mid-East NUTS 3 Region. There are now three NUTS 2 Regions which correspond to the Regional Assemblies established in the 2014 Local Government Act and are groupings of the new NUTS 3 Regions. The revisions made to the NUTS boundaries have been given legal status under Commission Regulation (EU) 2016/2066. The new NUTS 2 and NUTS 3 structure and classification are displayed in the table below:



