The number of people emigrating annually from the Republic fell for the first time below 20,000 in the year ended April 2001, according to Central Statistics Office estimates.
The figures, published yesterday, show a continuing upward trend in net migration with fewer people emigrating and more Irish nationals returning home. The number of emigrants in the year ended April 2001 was estimated at 19,900. This represents a 10 per cent drop on last year and a 50 per cent drop on 1999. Meanwhile, immigration in the same year was estimated at 46,200, an increase of almost 4,000 on last year.
Returning Irish nationals continue to be the largest immigrant group (39 per cent) although their share has been decreasing steadily from a 1999 level of 55 per cent.
US nationals represented 6 per cent of immigrants, UK nationals 15 per cent and other Europeans 13 per cent. Nationals of other countries accounted for over 26 per cent of immigrants. Last year, they represented only 18 per cent.
The CSO figures also showed a natural increase in population (births less deaths) of 25,700. This was the largest rise since 1988, when an increase of 26,300 was recorded. This boost, combined with the migration changes, has led to an increase in the Republic's population to a 120-year high of 3.84 million.
The highest population on record for the 26 counties was 6.53 million in 1841, falling to 3.87 million in 1881 and an all time low of 2.82 million in 1961.
The CSO has predicted the population will continue to rise, breaking the 4 million mark in 2005-2006, and reaching 4.57 million in 2031.
CSO statistician Mr Francis McCann said: "Neither the birth rate nor the death rate has changed very much but there are more women of child-bearing age in the State at the moment."
The number of women in the 25-29 age bracket stood at 166,400 in the year ended April 2001, compared to 162,100 in the previous year. There were also more women in the 30-34 age bracket - 156,800 in the year ended April 2001 compared to 149,500 the previous year.
As in previous estimates, immigrants were older in general than emigrants. Half of emigrants were aged 15-24, while 53 per cent of immigrants were aged 25-44.
Of the net immigrants, the CSO estimated that about 12,000 to 15,000 would be part of the labour force, making up about a third of labour force growth in the year, despite slower employment growth.