“COVID-19 has caused some unusual and unprecedented travel patterns,” Stats NZ senior demographer Kim Dunstan told AAP.
“We’ve had people that have been in New Zealand prolong their stay which has given some boost to migration.
“We’ve also had more New Zealand citizens returning from living overseas in recent months.
“And we’ve also had fewer citizens departing New Zealand to live overseas.
“The combined impact has seen an upswing in migration which has helped New Zealand reach that five million milestone.”
New Zealand grew from four to five million in 17 years, the quickest rate of growth in the country’s modern history.
That’s despite a major brain drain following the global financial crisis in 2008, when New Zealand’s net migration levels dipped into negative territory for the only time this century.
Migration has since rebounded to be as strong as ever, in real terms.
Still, Stats NZ believe population growth patterns over the last two decades – including the sugar-hit of recent months – aren’t likely to be matched in the next two decades.
“New Zealand has an ageing population and the latest projections do indicate that we’re likely to reach six million in the 2040s given the slowing in our rate of natural increase,” he said.
Demographers worldwide now face the unenviable task of re-modelling their migration patterns based on COVID-19 and its associated recession.
And then there’s the small matter of what Kiwis were up to in the bedrooms during their 51-day lockdown, which only ended last week.
“There has been some speculation that we might see a baby blip,” Mr Dunstan said, though he is sceptical.
“Couples tend to make childbearing decisions on broader considerations, like jobs and financial security.
“But it will be interesting to see what the birth numbers are in early 2021.”