KEY POINTS:
A continued weakening in the net inflow of migrants could be good news for the Reserve Bank but is unlikely to have any effect on short-term decisions about interest rates.
Statistics New Zealand says seasonally adjusted net permanent and long-term immigration was 630 people in March.
That continued the weaker trend of 520 in February and 410 in January. The number had been more than 1000 a month from June to December.
National Bank economist Philip Borkin said it was positive news for the Reserve Bank. "It will provide less impetus to the housing market and consumer spending going forward but the thing is there's a huge lag involved in that process.
"That is not expected to translate into an easing in residential investment and construction activity until later in 2008."
The Reserve Bank's focus would still be on inflation pressures and signs that the domestic economy was still very strong, Borkin said. The latest numbers were unlikely to affect next week's decision on whether to raise interest rates.
The number of New Zealanders leaving the country for at least 12 months, 49,845, was the highest for a March year since 2001, while 23,667 Kiwis returned home - the lowest number since the same year.
Net immigration of non New Zealand citizens was the highest for a March year since 2004 at 38,259 people.
Unadjusted annual net immigration for the year ending March was 12,080 people - down from 13,150 in February.
The volatile nature of the data made it hard to say whether the softening in net immigration was the start of a longer-term trend, Borkin said.
"It's hard to know what people's decisions are when they decide to permanently leave the country or to arrive in the country. It's not something that you can predict very easily," he said.
"If we do see a big shift in the labour market, if unemployment rates starts to pick up, if job security's not too high, you may see more New Zealanders start to depart overseas to countries that have a relatively stronger labour market."
Seasonally adjusted short-term visitor arrivals fell by 1 per cent between February and March.
"But when you look at a trend over the past 18 months they've held up very well and that suggests that New Zealand is still a reasonably popular destination for overseas visitors," Borkin said.
Making the journey
* A net 630 long-term arrivals in March.
* June-December migration was above 1000 a month.
* Expected to ease pressure on economy.
* Too early to determine a long-term trend.
* Unlikely to affect decision on interest rates.
