There have also been big falls in those aged under 25
The unemployment rate fell by 1.7% in April, with 4,600 fewer people on the Live Register.
Figures from the Central Statistics Office (CSO) show the seasonally adjusted total was reduced to 266,600.
The number of persons on the Live Register last month was the lowest number recorded in the seasonally adjusted series since October 2008.
In unadjusted terms, there were 263,417 people were signing on the Live Register in April - an annual decrease of 42,123 or 13.8%.
The figures also reveal the Live Register had a monthly drop of 2,700 men and 2,000 women in the same period.
Over the year, the number of male claimants also fell by 28,733 to 152,653, while female claimants decreased by 13,390 to 110,764.
The number of those on the Live Register long term in April 2017 was 111,807, giving an overall annual decrease of 26,376 in this category.
In terms of age, the number of persons aged 25 and over on the register in the year to April fell by 34,942 - and the number of persons aged under 25 also dropped back by 7,181.
The CSO says there have been annual decreases in persons aged under 25 every month since July 2010.
Irish nationals accounted for 82.6% of people on the register in April.
Of the 45,910 non-Irish nationals to register, the largest group was nationals from the 28 EU states - at 25,793 - followed by the UK at 10,054.