Ireland's older population will almost double over the next two decades, new figures have shown.
As life expectancy rates rise with the average woman predicted to live until 87 and the average man until 83 come 2031, the Central Statistics Office (CSO) predicted the population of Dublin alone could rocket by between 96,000 and 286,000.
The projections were based on birth and death levels across the country's eight regional authorities and the potential of people moving from one area to another between 2016 and 2031.
"The report is not an attempt to predict the future, but rather presents how the population of the various regions will evolve under different scenarios by making assumptions about future trends in migration, both internal and external, and fertility," the CSO said.
The Greater Dublin population, made up of the capital and the Mid-East regions, is projected to have risen by between 174,000 and 401,000 in 18 years' time.
This could see an annual population increase in Greater Dublin of up to 20,100 each year.
One scenario considered by the CSO would see the number of over-65s almost double across every region between 2016 and 2031.
The most marked increase would occur in the Mid-East with a hike in pensioners of 136.5%.
The number of over-65s in the Midland region is expected to increase by 95.1%.
Meanwhile, on a national level, men are expected to live an average four and a half years longer by 2031 than they were in 2011, and women by over three and a half years.
As people move from one region to another, some areas will see a population rise that is disproportionate with births.
For example, while the Border region has projected births of 123,000, its population will increase by just 18,000, and while the West has projected births of 97,000, its population is likely to rise by just 15,000.
Elsewhere, one scenario envisaged by the CSO will see the number of young people aged from birth to 14 increasing in the Mid-East by 4.7% between 2011 and 2031, while all other regions will experience a decrease in the population of this age group.