The 2006 Irish Census 2006 show significant changes to the population of most Mayo towns.
Castlebar now has a population of 10,655 according to Census 2006. The town saw population growth of 3.6 per cent in the last four years.
Ballina had a six per cent jump in population between 2002 and 2006. The population of the north Mayo town is now 10,056.
Westport saw a decline in population of 2.8 per cent; the town now has 5,163 inhabitants. The next largest town in the county, Claremorris, saw a jump in population of 23.5 per cent. It now has 2,595 inhabitants.
Ballinrobe saw its population grow by more than a quarter in the last four years. The south Mayo town now has 2,098 inhabitants and saw growth of 29 per cent since 2002. Ballyhaunis is the 6th largest town - and has a population of 1,708 according to the Central Statistics Office, which means a jump of 23.7 per cent in 5 years
Population growth for other East Mayo towns was not as marked. Swinford has 1,502 inhabitants, but saw growth of just 0.3 per cent. Kiltimagh saw more significant growth, at 9.6 per cent, taking its population to 1,096.
The next largest town in the county, Belmullet, saw its population grow by 12.8 per cent to 1,074. Foxford, with a population of 1,058, experienced growth of 20.5 per cent between 2002 and 2006, according to the CSO.
Knock now has 745 inhabitants, and saw a 25.2 per cent rise in its population since 2002. Charlestown saw a 10.2 per cent jump in population, with 745 inhabitants. Newport now has 590 residents, and saw population growth of 12 per cent.
Smaller towns which experienced a very high rate of growth in the last four years include Balla, whose population increased by 32.3 per cent. There are now 586 people living there.
Shrule grew by 30.4 per cent. It now has a population of 425. Kilkelly saw the highest rate of growth of any Mayo town at 69.1 per cent. The town now has 389 inhabitants, according to Census 2006. Louisburgh, meanwhile, saw its population more than double. It now has 314 inhabitants, after growth of 51.7 per cent.
Bangor Erris now has 295 residents, after population growth of close to 11 per cent.
Elsewhere, the population of Crossmolina dropped by half a percentage point to 930. In Killala, a drop of 12.5 per cent in population was recorded, leaving the population at 569. Gob an Choire (Achill Sound) saw its population drop by almost 15 per cent, leaving 302 residents.
Ballindine experienced a population slide of just over 16 per cent, leaving 249 inhabitants. Ballycastle now has 215 inhabitants after experiencing a drop of almost 14 per cent. Kilmaine saw a 22.8 per cent drop in population, leaving 142 inhabitants. Cong saw the largest population drop of any town in Mayo with a fall of just over 30 per cent. The population is now 101, according to the CSO.