A number of countries around the world are experiencing population decline, or depopulation.
Japan, for example, saw a population loss of 644,000 in 2020 to 2021, and its population is expected to decline by 30 percent in the next 40 years, and then halve by the end of the century.
It is estimated that 23 countries will see a halving of their population between now and 2100.
Demographer Paul Spoonley of Massey University says countries need to be ready for the change.
In most of northeastern Europe, most of southern Europe and in South Korea and Taiwan, population growth is declining, Spoonley says.
Declining population is driven by declining fertility, he says.
“If you look at the European countries I’ve mentioned, their fertility tends to be down at those 1.2 to1.3 births per woman and...you need 2.1 births per woman to replace your existing population.”
Germany has more deaths than births each year, and has had for the last 50 years.
Refugees have kept population numbers in some countries higher.
“It’s really that migration inwards, especially in regards to refugees, and the same applies to Scandinavia.”
Poland and Hungry have seen an influx of Ukrainian refugees but this is a short-term hit, he says.
There are countries that are growing though, and Spoonley says the global population is expected to grow until mid-century.
“There are huge assumptions in this...but by the end of the century it’s quite possible that Nigeria will be almost the same size as China.”
The two “super-sized populations” of India and China have very different trajectories, he says. India will keep growing, China will not.
Pre-Covid-19, New Zealand was growing at 2.1 percent when the OECD on average was 0.6 percent. Now we’ve dropped below the OECD average, to 0.2 percent, Spoonley says.
“People are leaving New Zealand, typically New Zealand citizens, so we’re going back into what’s been a historic pattern, but we still haven’t got many migrants to replace those departing New Zealanders.”
Labour force - the number of people in the working age group – is one of the big problems. The supply simply doesn’t match the demand.
“Many of the countries we’re talking about have got an aging population so the question throughout, which has been really really highlighted throughout Covid has been where do we get our workers from when we’ve got these big shortages?”
The short-term fix is always going to be to get more migrants, he says, but this doesn’t deal with long term issues.