Annual wage growth, including overtime, grew 3.3% for the year but on a quarterly basis increased just 0.6%, its lowest rate during the past two years.
The slowing signals a peak in wage growth, and labour costs trending down.
Statistics New Zealand yesterday released its labour cost index figures for the quarter ended March.
In it, the education, mining, health and agriculture sectors enjoyed the biggest rises.
ASB chief economist Nick Tuffley said the private sector overtime-inclusive measures, at 3.1% year-on-year, "exactly matched" the Reserve Bank forecast made in March.
"As the labour market softens there will be further moderation in wage growth over 2009 and 2010," Mr Tuffley said.
The unadjusted labour cost measures, before adjustments for changes in job quality such as promotions and productivity, reinforced that wage growth had peaked and would trend downward, he said.
"The sectors experiencing the strongest wage cost growth were education and health, with collective wage agreements taking effect," Mr Tuffley said in a statement.
The private sector measure registered annual growth of 5%, down from its 5.5% peak in the first half of 2008, while the combined public/private measure also eased to 5.2% from its 5.6% peak late last year, he said.
"Business surveys are among the early warnings that the labour market has started to soften gradually in response to the drawn-out recession," Mr Tuffley said.
He said today's household labour force survey would provide greater insight into the extent to which the labour market had weakened in early 2009, with lower employment and higher unemployment.
"It will be a guide to how quickly wage growth will ease ahead," Mr Tuffley said.
The household survey is expected to reveal a gain in unemployment from 4.7% to 5.3%, following hard on the heels of a New Zealand Institute of Economic Research paper released on Tuesday warning an extra 50,000 New Zealanders may be unemployed within the next year.
Monday's separate Quarterly Employment Survey showed a continued decline for labour during the same first quarter, with a 1.7% decline in full-time equivalent employees and seasonally adjusted total paid hours down 0.4%.
