The Covid-19 pandemic may cause a halt in migration to New Zealand for up to four years, a demographer says.
Yesterday, Statistics New Zealand released population estimates that showed the nation numbered 5,002,100 people on 31 March.
It came amid the pandemic, which is affecting travel and migration.
Massey University's Distinguished Professor Paul Spoonley, a demographer, told Morning Report he did not expect things to go back to normal any time soon.
"In terms of tourists and migrants, we're probably looking at a halt for two, three, or four years."
He said New Zealand had many of the values that the growing global middle class looked for - and he expected that group's migration to Aotearoa would resume quite soon.
"We might not grow as fast but certainly, I would anticipate migrants coming to settle and live here over the next five years."
Reaching 5 million was the fastest million in the country's history - taking just 17 years to grow from a population of 4 million people in 2003.
"It's partly because we still have quite high levels of fertility, so the first 10 years of that 17 years (since we hit 4 million) we've seen births contributing to population growth, ... the big story in town for the last seven years is migration ... it's added well over a quarter of a million people to our population," Spoonley said.
When it came to birth rate, New Zealand was one of the last OECD countries to go sub-replacement, he said.
Statistics New Zealand defines replacement fertility as "a total fertility rate of 2.1 children per woman, which equates to the average number of children each woman is required to have for a population to replace itself in the long term, without migration".
"We are at 1.7 and we arrived there at 2017, so we are late to the party but we are certainly seeing fertility dropping and I would anticipate, by the way, that this pandemic will contribute to that drop," Spoonley said.
"I think economic uncertainty combined with public health concerns will see a drop in our births nine months from now."
Māori fertility was much higher than Pākehā fertility, despite still dropping, he said.
Looking forward, forecasting showed over the next two decades, Auckland would be the recipient of 60 percent of our population growth.
"Sometime in the next decade, about 40 percent of New Zealanders will be living in Auckland, and that's a big policy and political question - is that something that we want to see?"
That pressure on infrastructure has been twofold - many migrants come into a city like Auckland ... but the other thing is that ... there has been a significant number of people coming in temporarily both as tourists and temporary workers.