Provisional migration data suggests net inflows may continue to strengthen through the rest of 2019, ASB senior economist Mark Smith says.
While the latest Stats NZ data is subject to revision, it suggests the country gained a record 6,570 permanent long-term migrants in February. For the 12 months through February the estimated net inflow 61,576 would be the highest in 26 months, Smith said.
"If correct, this will have widespread market and policy implications," he said in a client note.
"Looking at recent historical data suggests that net immigration inflows are continuing to trend up.
"We continue to expect that annual net PLT immigration will eventually moderate but the recent data suggests the strengthening trend is likely to continue for a while yet. We note that the volatility and monthly historical revisions in the figures make it difficult to predict how quickly our resident population will grow."
The government statistician formally changed the way it measures migration in November, no longer relying on arrival and departure cards which the government no longer requires travellers to complete. It said the card-based data hadn't been accurate because it only captured travellers' intentions and not what actually happened.
Infometrics said, while the February estimate is more consistent with those released in January, the firm remains "deeply sceptical of an apparent radical swing in migration."
It noted that since the new estimates have been published the outlook for net migration has swing from a plunge in November's data, to a stable outlook in December's data to accelerating upwards in the past two months.
"The sharp upswing in net migration estimates goes against all other indicators: government restrictions on migrant entry have been tightened further, and visa approvals are weaker."
Brooke Theyers, Stats NZ's population insights senior manager, said the new modelling means "revisions may be significant in the first few months after initial release."
"That means net migration data is most valuable when put in the context of a longer time series," and the numbers will become less subject to revision four or five months after they're first published, Theyers says.
The data from previous months does show significant revisions. The figure for the year ended January has been revised upwards to 58,657 from the previously published 58,391 while the figure for calendar 2018 has been revised to 56,908 from the 48,300 published in February.
Theyers says the figures for the 12 months ended February of a net gain of 61,576 people, up from 51,645 a year earlier, could move up or down by 1,800 people.
She acknowledges that in previous months "arrivals were higher than first estimates and departures were lower."
That meant the figure for the 12 months ended September, for example, – which remains provisional – is now 52,200 - 6,600 higher than first estimates.