The influx of young migrants into Ireland may be a significant factor in keeping upward pressure on house prices, economic experts have said.
The comments follow the publication of new figures which showed that over a quarter of a million people have come to live in Ireland in the last six years, according to the latest figures from the 2002 census.
It has also emerged that up to 30,000 more people moved to Ireland in the 12 months to April 2002 than previously estimated.
The combined forces of returning emigrants, foreign workers and asylum-seekers have also created a situation where in one in every six people in Ireland has lived abroad for at least one year.
The latest volume of the census, taken in April last year, shows that 644,400 long-term migrants are now living in Ireland. Of these, 366,800 are returned Irish emigrants, while 252,000 of them have come here to live since 1996.
The phenomenon of returned migrants is particularly pronounced in counties which were decimated by emigration during the 20th century.
Twenty-two per cent of people living in Mayo have lived abroad for at least one year, 21 per cent in Donegal and Leitrim and 20 per cent in Galway.
Ninety per cent of those living in Ireland were born here, according to the report, while 183,000 or 5 per cent of the population were born in England and Wales.
In recent times, migration into Ireland is now being driven by foreign nationals rather than returning emigrants.
In the 12 months before the census, 76,000 people moved into the State, two-thirds of them born outside Ireland. Just over 44 per cent of these people were aged between 20 and 29, two-thirds of them being single.
The figure of 76,000 is nearly 30,000 more than the last available estimate from the Central Statistics Office (CSO) for migration levels in the same period, according to Mr Dan McLoughlin, chief economist with the Bank of Ireland. He says the CSO had been estimating migration levels of 47,500 for that period.
According to the latest report, 20- and 30-somethings are also the most ethnically diverse generation in the country, with one person in 10 in the 25-34 age bracket described as non-Irish nationals.
Overall, 5.8 per cent of the population are now non-Irish nationals. The highest concentrations of non-national residents is in Dublin where 7.2 per cent of the population is non-national,while 6.9 per cent of residents in Co Clare are non-nationals, and 6.8 per cent in Kerry.
The counties with the smallest non-national populations were Offaly with 3.6 per cent and Laois with 3.8 per cent.
Mr McLoughlin also believes the high numbers of migrants in their 20s and 30s may also be a factor in maintaining housing demand and house prices.
"It looks like 65,000 houses will be built in Ireland this year and this migration pattern might explain the continuing demand for housing."
The rising numbers of non-nationals have led to calls for the Government to mount an information campaign to encourage foreign nationals resident here to sign on to the electoral register in the run up to June's local and European elections.
Under Irish law, any person resident in Ireland for more than 12 months is entitled to vote in local elections. Any European Union citizen, including those from candidate countries, is also entitled to vote in the European elections.