Permanent and long-term (PLT) arrivals outnumbered departures by 300 in December, down from 1400 a year earlier, Statistics New Zealand (SNZ) data released yesterday showed.
The main factor in the decline was the 900 more departures by New Zealand citizens to Australia in the month, with the net outflow of 2000 migrants to Australia in December, up from 1100 a year earlier.
Net inflows of 1200 migrants came from Britain and 200 came from India.
For the whole of 2010 the net PLT outflow to Australia was 21,000, above the 2009 outflow of 18,000, but still well below the outflow of 35,400 in 2008, SNZ said.
During the latest year there were 36,800 departures to Australia offset by 15,800 arrivals from Australia.
In both directions, most migrants were New Zealand citizens.
ASB economist Jane Turner said the December lift in the New Zealand unemployment rate highlighted the divergence in labour market performance between the two countries.
"We are likely to see a steady stream of New Zealanders leaving to Australia for the time being."
Permanent arrivals appeared to be stabilising, although remained relatively subdued, she said.
The country providing the highest net inflow of migrants was India with 6300, with almost three-quarters of migrants arriving from India having student visas.
The net inflow from Britain dropped to 5300 in 2010 from 9100 the year before, while the net inflow from China last year was 3600.
The 82,500 PLT arrivals in 2010 were down 5% from the 2009 figure, while the 72,000 departures were up by 11% on 2009.
On a seasonally adjusted basis there was a net migration gain of 800 in December, up from 600 in November and above the monthly average of 700 since February, SNZ said.
In the Canterbury region, where an earthquake in September caused widespread damage, PLT arrivals were up 3% in December from a year earlier.
Increases in natural and physical science professionals including geologists and geophysicists, and in bricklayers, carpenters, and joiners contributed to the increase into Canterbury compared with December 2009.
Ms Turner said migration was likely to remain "relatively low" but steady for the rest of the year.
Growing shortages of skilled labour might see arrivals of migrants on work visas lift towards the end of the year.
However, Australia's labour market was likely to remain relatively attractive across many different industries and skill levels.
"The low level of migration contributes to slowing population growth, reducing demand for new housing construction. The recent weakness in net migration is likely to be a key driver of low building consent issuance to date."
