The world’s population will start to fall by mid-century. The time to prepare is now

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The evidence is now irrefutable to everyone except the diehards at the United Nations Population Division and their neo-Malthusian allies. The human population will not keep growing, as the UN asserts, but will instead peak by mid-century and then start to fall. We need to plan for this much smaller world, a world filled with many who are old and few who are young.

The latest and most complete proof that such a future awaits us arrived this week in a report published in the scientific journal The Lancet.

Using methodology that takes into account changing levels of fertility, mortality, migration, education and availability of contraception, a research team led by Christopher Murray, director of the Institute for Health Metrics and Evaluation at the University of Washington’s School of Medicine, concludes that the planet’s human population will peak at 9.7 billion in 2064, and then start to drop, reaching 8.8 billion by 2100.

This starkly contradicts UN projections that the human population will grow to almost 11 billion in 2100 from today’s 7.7 billion. If the Lancet study is correct, two billion people just disappeared from the Earth’s future.

John Wilmoth, director of the population division in the UN Department of Economic and Social Affairs, contests the report’s conclusions, saying countries with low fertility may find ways to increase fertility in the decades ahead.

But as co-author Darrell Bricker and I demonstrated in Empty Planet: The Shock of Global Population Decline, Mr. Wilmoth’s assumption contradicts the available data, which show that once a country’s fertility rate drops below the replacement rate of 2.1 children per woman on average, that rate stays low and usually trends even lower. The Lancet study offers robust new evidence to support that argument.

The forces that will shape future population trends are influencing economies and great-power rivalries right now. The Lancet study predicts that China’s population will crater by almost 50 per cent over the course of this century, falling from 1.4 billion in 2017 to 732 million in 2100, because of its low fertility rate. That drop will begin in just a few years.

India’s population will have dropped from 1.4 billion to 1.1 billion by century’s end, although it will still have the largest working-age population in the world. Russia will be down to 106 million, from 146 million today.

Over the same period, the population of the United States will grow from 325 million to 336 million, because the U.S. is able to compensate for low fertility through immigration.

Similarly, the study projects Canada’s population will rise from 36 million to 44 million. Given our robust immigration targets, that figure seems low to me, but it is still well ahead of Italy (31 million) and Spain (23 million). Spain is one of 23 countries – including Thailand and Japan – that will lose more half its population this century. By 2050, 151 countries will have a below-replacement fertility rate.

Humanity will also be much older, with 2.4 billion people over the age of 65 and only 1.7 billion under 20.

“Our forecasts for a shrinking global population have positive implications for the environment, climate change and food production,” the authors conclude, “but possible negative implications for labour forces, economic growth and social support systems in parts of the world with the greatest fertility declines.”

Although falling fertility is something to celebrate – it results from women acquiring greater control over their lives and bodies – the economic strain is great, with ever-fewer young people around to drive growth and pay for the needs of old people.

To keep pensions and health care systems sustainable, we need to raise the retirement age and require higher mandatory pension contributions, while expanding and improving long-term care, especially the wages of those who provide it.

Canada should also increase its immigration intake well beyond the 341,000 who were slated to arrive this year, before borders closed. And we need to improve parental leave and supports for child care, to encourage young couples to have as many children as possible.

We’ve never lived in a world where the human population steadily and deliberately drops every year. There will be challenges and opportunities we haven’t even imagined yet.

A decreasing population isn’t a good thing or a bad thing. But it is a very big thing. We need to prepare.

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