Ireland has the fastest growing population in the EU, driven mainly by continuing high levels of immigration.
In the latest figures published by the Central Statistics Office (CSO), the overall population is estimated to have increased by more than 100,000 in the space of a year, bringing the overall number of people living in Ireland to 4.34 million. The population is now at its highest level since records began in 1861.
The pace of such rapid population growth, which far outstrips the EU average, illustrates the scale of the challenge facing the Government in responding to pressure on schools, infrastructure and health services.
Nearly two-thirds of the population increase was due to net immigration. An estimated 109,500 people migrated into Ireland, while about 42,200 left the country, resulting in net immigration of 67,300.
The rest of the increase was accounted for by a natural increase - the number of births minus the number of deaths - of 38,800. The natural increase recorded for the last year is one of the highest in Ireland in about 25 years.
The overall population rise of 106,000 people represents an increase of 2.5 per cent between April 2006 and April 2007. This increase is well above the next fastest growing EU state, Spain (which recorded an increase of about 1.64 per cent last year), followed by Cyprus (1.6 per cent).
Aidan Punch, a senior statistician with the CSO, said the rapid increase will inevitably have major public policy implications.
"It's an enormous challenge when your population is increasing year-on-year, by 2.5 per cent, not just in one year, but three in a row. A 7.5 per cent increase in population does place a strain on the system, I think," he said.
"Policy makers will look at the figures and see the extent to which they may have to amend policies in areas like education and infrastructure."
Figures also show that almost half (48 per cent) of the immigrants who arrived into Ireland in the last five years were from EU accession states such as Poland.
Most immigrants (55 per cent) were aged 25-44, while a further 28 per cent were aged 15-24. Around one in 10 of the immigrants were children under the age of 15.
Meanwhile, the CSO's figures indicate that, even without inward migration, Ireland has a fast-growing population.
The natural increase in the population has doubled from 16,600 in the 12-month period ending April 1994 to 38,800 in the corresponding period to April 2007.
Other data shows that women in the Republic are continuing to have more children than women in most other EU countries, despite high childcare costs and record numbers of women in employment. Irish women have an average of 1.9 children, compared with Finland (1.8), Germany (1.3) and Poland (1.2). Only France has a higher fertility rate (1.94).
Overall, CSO officials said yesterday that they were satisfied with the quality of census data last year which estimated that the number of foreign nationals in Ireland has doubled to about 420,000, or 10 per cent of the population, in the past four years.
A number of representative groups have queried the data, saying that it significantly underestimated the number of foreign nationals here. Census data for last year found UK citizens accounted for most non-Irish nationals resident here (112,548), followed by citizens from Poland (63,276), Lithuania (24,638), Nigeria (16,300) and Latvia (13,319).