CSO Frontier Series outputs may use new methods which are under development and/or data sources which may be incomplete, for example new administrative data sources. Particular care must be taken when interpreting the statistics in this release.
Learn more about CSO Frontier Series outputs.
This chapter of the IPEADS 2021 research paper shows how the methodology uses administrative data to produce experimental population statistics. Many of the underlying trends that are seen in the census are also seen in these statistics. In some cases, there are notable differences between what has been produced here and what we see in the census and other surveys. This mainly happens because the methods of data collection and analysis are very different.
The experimental methodology used to compile the following statistics is outlined in greater detail in the methodology chapter. Using this methodology, the population of Ireland was estimated to be 5.28 million in April 2021. This estimate is produced using data collected from administrative records only and applying a set of ‘rules’ to decide whether a person is likely to be usually resident or not. Applying a population concept of usual residence to data collected from administrative records is challenging and the CSO are undertaking further analysis to improve the accuracy of these estimates. It may take several years of refinement and commitment across the broader public sector through the National Data Infrastructure, before the CSO has sufficient confidence that these estimates play an integral part in the production of official population statistics.
The number of males and females in 2021, by single year of age, is represented in the population pyramid in Figure 2.1. There were high numbers of births in the late 1970s and early 1980s. The children born then were in their late 30s and early 40s in 2021 and are the main contribution to the bulge in the middle of the population pyramid. Another contribution to this cohort is as a result of strong inward migration of 20 to 30 year olds starting in the late 1990s up until 2009. Even though the number of births peaked at 74,000 in 1980 the number of persons aged around 40 in 2020 is estimated to be about 89,000 reflecting the net inward migration. This cohort then drove the high birth rates from 2007 on, peaking at over 75,000 in 2009.
Low birth rates in the late 1980s and 1990s combined with net outward migration between 2010 and 2014 has resulted in the smaller population of persons in their teenage years and 20s. As a result, we have seen a drop off in births recently reflected in the shape of the pyramid from age 10 and under.
The interactive population pyramid below shows how the age structure of the population differs across Ireland. In very urban areas such as Dublin City, Galway City and Cork City there are relatively fewer children and large cohorts of young adults. Whereas in more suburban and rural areas there are higher proportions of children and adults in their 30s and 40s. This difference in the population structure is particularly noticeable when comparing Cork City and Cork County for example.
As Eircode coverage improves on administrative data it is increasingly possible to produce statistics at lower levels of geography than Local Authority. While gaps still exist Eircode coverage is improving and estimates at Local Electoral Area (LEA) are becoming more robust. Extreme caution is still urged when using these figures as not all records have an Eircode and the gaps in coverage are not equally spread across all LEAs.
Dependents are defined for statistical purposes as people outside the normal working age of 15-64. Dependency ratios are used to give a useful indication of the age structure of a population with young (0-14) and old (65+) shown as a percentage of the population of working age (15-64).
The total dependency ratio stood at 51.2% for the State. When examined by gender the results show total dependency was higher for women, at 52.0%, than for men at 50.4%, this difference is driven by the gap in the old dependency ratio for women (23.0%) compared with men (20.5%). The young dependency ratio is similar for women and men.
Young dependency, shown in Map 2.2, is the number of young people aged 0-14 as a percentage of the population of working age, stood at 29.4% for the State. Dublin City had the lowest young dependency at 22.0%, followed by Galway City at 23.6%. Laois had the highest young dependency at 33.4%, followed by Meath and Cavan at 33.0%.
Old dependency, the number of older people aged 65+ as a percentage of the population of working age, stood at 21.7% for the State. Map 2.3 shows that counties of the North West, Kerry and Dún Laoghaire-Rathdown recorded the highest old dependency ratios between 26.1% and 28.4%. Fingal (15.5%) and Kildare (17.1%) recorded the lowest old dependency ratios.
The average age of the population is estimated to be 38.0 years in 2021. Fingal recorded the youngest population at 35.5, followed by Kildare at 36.3. Dún Laoghaire (40.2), Kerry (40.1) and Mayo (40.0) have the oldest populations. Map 2.4 shows average age of the population for each Local Authority.
At 38.5, the average age for women was one year older than men who had an average age of 37.5. When examined by sex, the average age for women is higher in all county and city administrative areas.