This new experimental report produces the first estimates of migration based on administrative data. The publication is categorised as a CSO Frontier Series Output and so care must be taken when interpreting the statistics in this release.
A Frontier Series output may use new methods which are under development or incomplete data sources, for example, new administrative data sources. These new outputs allow the CSO to provide useful new information to users and get informed feedback, while at the same time ensuring that limitations are well explained and understood.
The administrative data used in the experimental analysis was not originally created to measure migration flows. However, this report aims to estimate migration flows, aligned with official definitions as closely as possible, by suggesting residency based on different administrative record activity rules and illustrating the results from the respective methodological approaches adopted.
The length of stay is not directly measured in many administrative datasets and has to be inferred. For example, if a student is enrolled in third level education for an academic year, it is assumed they were present in two calendar years. As such, the experimental methodology in this report does not strictly adhere to the official definition for migrants, as short-term migrants are included in the immigration and emigration estimates. With the advent of new real-time administrative data sources, it will be possible to measure activity within and across years more accurately in future.
Utilising administrative data ensures maximising value for money for the public. Under the auspices of the Statistics Act 1993, and in compliance with all relevant data protection legislation, the CSO is in a unique position to gather and link administrative data sources held by Government departments and agencies and evaluate their potential for statistical use.
The demand for data and insight into Irish society continues to grow unabated. The growth is not just apparent in terms of the broad range of themes (e.g. globalisation, productivity and well-being) that Official Statisticians are being asked to provide information on, but also in relation to the level of detail being required in the analysis (e.g. sociodemographic variables). Clearly the range and depth of demand for data cannot be met from survey data alone. Analysis of new data sources is needed, including administrative records held by Public Sector Bodies.
Not all migrants are active in the available administrative data held by Government departments and agencies – an example would be non-Irish national immigrants enrolled at language schools who are also not in the labour force.
Another issue is the length of stay in the State is not directly measured in many administrative datasets and has to be inferred.
Further improvement in data coverage, and additional real-time data sources becoming available would enhance the methodology in this experimental analysis. The more data that can be incorporated, the more precise the figures will be. For example, the collection and coverage of Eircodes has improved in recent years, facilitating improved geospatial analysis
The data used to calculate the Official estimates is very different to the data used for the experimental estimates. Official estimates are primarily based on responses from respondents in the Labour Force Survey, while the experimental methodology presented in this report uses administrative data sources. The Official migration estimates are subject to revision once the results of the next census become available, because following each census the Official and definitive inter-censal net migration is derived. Immigration flows for census years in the Official estimates are obtained from responses to the Census of Population.
Also, the experimental methodology includes short term migrants and excludes some economically inactive migrants, but is expected to improve in the future, as more administrative data and more real time data becomes available.
Migrants need to be recorded in administrative systems to be included. Pseudonymised administrative data was used from several sources, including Revenue, the Department of Education and the Department of Social Protection.
For the annual methodology around six million unique records were pooled. This was done in order to determine who in the population met the criteria to be included in the measurement of migrants flows, utilising the methodology described in this report.
All information supplied to the CSO is treated as strictly confidential. The Statistics Act, 1993 sets stringent confidentiality standards: Information collected may be used only for statistical purposes and no details that might be related to an identifiable person may be divulged to any other government department or body.
As per GDPR Article 4(5) " ‘pseudonymisation’ means the processing of personal data in such a manner that the personal data can no longer be attributed to a specific data subject". In other words, individuals cannot be identified in pseudonymised data.
The CSO never shares any personal data with any third parties whether they are private entities, commercial operations or government departments.
Learn about our data and confidentiality safeguards, and the steps we take to produce statistics that can be trusted by all.