The population drift to Australia reached its highest level in at least 30 years last month.

Figures published on Wednesday by Statistics New Zealand (SNZ) showed about 47,200 people left New Zealand for Australia on a permanent or long term (PLT) basis during the year to September. About 13,200 came the other way.

The resulting net PLT outflow to Australia of around 33,900 was the highest for any 12-month period since monthly figures started to be compiled in April 1978, SNZ said.

The net outflow to Australia compared with 26,200 in the September 2007 year and was higher than previous peaks of 33,700 in the January 1989 year and 33,400 in the December 1979 year.

For the month of September, the net outflow of 2400 PLT migrants to Australia was up from 1800 a year earlier.

New Zealand’s overall annual migration net gain has also fallen to its lowest level in nearly seven years.

In the year to September, 86,700 people arrived in this country on a PLT basis, while 82,300 left, SNZ said.

The resulting net PLT gain of 4400 was down from 8300 in the September 2007 year, and the lowest since the October 2001 year.

The number of arrivals was actually up 3700 or 4 per cent from the previous year, but that was overshadowed by the 7600 or 10 per cent increase in departures.

For the month of September the net PLT gain of 1700 people was down from 2200 a year earlier. Seasonally adjusted PLT arrivals matched departures last month.

National Party finance spokesman Bill English said the statistics were a reminder that New Zealand had major fundamental economic issues that were around long before the current international crisis.

The increasing pace of the exodus showed New Zealand needed to grow so New Zealanders could earn higher wages and have a better quality of life in this country, he said.