New figures show average weekly earnings dropped by 1.1% in the second quarter of this year, compared to the same period last year.
The Central Statistics Office reports a 0.3% decrease in the private sector from €623.79 to €622 a year earlier.
It also shows a drop of 1% in the public sector from €928 to €918.
However, across the economic sectors, average weekly earnings increased in seven of the 13 sectors - with the largest percentage change recorded in the construction sector - up 6% from €698.27 to €739.96.