Migration depleted our population again in July, the fifth month in a row to record a decline.
Permanent and long-term migrant departures (those leaving the country for at least a year) exceeded arrivals (those who had been living overseas for a least a year) by 220 on a seasonally adjusted basis, Statistics New Zealand reported.
And for the year ended July, the net inflow of migrants was just 2900, the smallest annual gain for 10 years. That compares with a net gain of 15,200 the year before and an average gain of 12,000 for the past 20 years.
The dwindling net inflow of migrants has had a real impact on overall population growth.
The population rose by 37,500, or 0.9 per cent, in the year ended June compared with an average increase of 1.3 per cent for the past 10 years.
Since the February earthquake 4200 Christchurch people have left not just the city but the country, 1700 more than the same period last year, while 1800 people arrived from overseas to settle in Christchurch, 800 fewer than the same period last year.
But the biggest change is a resurgence in migration to Australia - a net outflow of 3200 last month, 3100 of them New Zealand citizens.
In the year to July a net 32,600 people left for Australia, up from 16,500 the previous year and a 10-year average of 21,000.
But ASB economist Jane Turner expects outflows to Australia to peak in the coming months.
"Australia's labour market has slowed considerably over recent months. Meanwhile, economic pros-pects in New Zealand have improved, job growth now showing a firm recovery, which should convince some [Kiwis] to stay put - at least while the Rugby World Cup is on."
The migration outflow reduced inflation pressures by reducing demand for goods and services and relieving some of the stress on a tight housing market, Turner said.
BNZ chief economist Tony Alexander said changes in population growth tended to lag behind changes in economic growth. "That suggests a lift in population growth is likely from early next year."
Alexander expects the outflow of people to reverse in 2012 as labour and housing markets weaken in Australia but strengthen here.