As go China and India, so goes the world

How China losing the the top population spot to India helps us understand global trends

Welcome, new subscribers! This newsletter only comes out when I have something useful to say so it’s irregular, but generally twice a month. Hope you enjoy.

Credit: Arctic-Images via Getty Images

Astronomers tell us that we look to the night sky, we are actually looking back in time. Light from those far away stars takes so long to reach our eyes here on Earth that by the time we wish upon a particular star, it may no longer even exist. When I look at global population trends, I think about those stars. Last week, I was a guest on WBUR’s On Point* and made the bold claim that the population “problem” is solved, even though we’ll still add about another 2 billion to world population before we peak. The other guest disagreed, as most environmentalists do, but I stand firm. Here’s why I’m right.

*by the way, you can read an excerpt of my latest book on WBUR’s website

Reaching 8 billion and counting last November was remarkable, but focusing on that number and the march towards 9 and 10 billion means that we’re missing the most fundamental shift to ever take place in human population: the shift towards pervasive and permanent low fertility, population aging, and depopulation. When we track global population increase, we’re basically looking at a star that seems to be shining brightly, but in actuality has already exploded—or in this case, imploded.

That’s because there’s a difference between what’s happening on the surface with global demographic change and the tectonic forces underneath. When I try to explain this, in my mind I see a cross-section of the Earth where people are piling on top, but underneath is the tectonic force of changing fertility. I don’t have the artistic skills to illustrate this for you, but there’s a graph that does kind of the same thing: a population pyramid. Similar to the night sky, when we look at a population pyramid we are actually looking at the past. (Unlike the night sky, however, we are also looking at the present and future.)

This is the population pyramid for the total global population of 8 billion in 2023. The right axis lists the years in which people were born, and we see a divot around the time of COVID as many put off having children. On the left axis are ages in ascending order. But, what we really want to do is squint our eyes and lean away from the screen to look at the overall shape of the “pyramid,” which we can see is starting to resemble more of a stovepipe, with straight sides. That’s because global fertility is now a low of just 2.3 children born per woman in her lifetime, just a hair above replacement level. Reread that last sentence, because this is remarkable.

Global population may be growing, but we have a graying and—before we know it—shrinking world. The rate of global population change has been falling since the 1960s, as this figure shows.

The last few “billion” population milestones have been rapid, about every 12-13 years, but it will be two-and-a-half decades from now before we hit 9 billion. The global population is getting older, too. If we had lined up everyone in the world from youngest to oldest and asked the middle person to raise their hand in 1950, that person would have been 22 years old. Today, the middle person would be over 30, and by 2050 that person will be 36. So, we’re growing more slowly, and we’re getting older, but…we’re still growing, and that growth is what causes so much alarm among those in the environment, conflict, and development sectors. Why is what’s happening on the surface seemingly divorced from the underlying trends?

We can simplify to three components of present and future population growth. One part: there are more of us because we’re living longer—7 extra years just this century. Another part: Population is growing even in places with low fertility because of population momentum, something the UN highlighted in its most recent data release. Their wording was clear: “Two-thirds of the projected increase in global population through 2050 will be driven by the momentum of past growth that is embedded in the youthful age structure of the current population. Such growth would occur even if childbearing in today’s high-fertility countries were to fall immediately to around two births per woman.”

That’s notable because it reflects India’s experience, riding the momentum of past growth even as fertility is low. India is one of just 8 countries whose growth will drive more than half of the expected increase in global population between now and mid-century but India’s growth is baked in from the past, as we see in the following three population pyramids for India in 1998 (25 years ago), 2023, and 2048 (25 years from now). The India of 25 years from now is fairly certain. India’s median age will be about 33-34 years, up from 28 years today and 21 years in 1998 (an increase of 12 years over a 50-year timespan, and just a shade behind the global numbers). The mothers who will give birth between now and 2048 are already born and we have a good sense of their reproductive behavior (desired fertility in India is about 1.6 and right now actual fertility is 2.0, so we should expect a trend downward towards that 1.6). Given that, plus modest life expectancy increases so that there will be more older people in India, India’s population will add only 230 million over the next 25 years (yes, that’s a lot, but they added 430 million over the last 25 years, from a population of 1 billion in 1997). Look at how “stovepiped” India’s age structure is becoming as you view this 50-year time span. That’s where world population is headed, too.

You can play around with animating population pyramids at this cool website.

That third component of present and future population growth is exactly what you expect: fertility is still high in some countries. More than half of world population growth through 2050 will come from countries in sub-Saharan Africa. The region is on track to add nearly 1 billion people, assuming some fertility declines. Over 40% of that growth will come from just four countries: the Democratic Republic of Congo, Ethiopia, Nigeria, and Tanzania.

Several decades ago, when I started studying global population trends, societies with older age structures were the exception to the general rule. Today, it’s societies with high fertility that are the exception. Since two of every three people in the world today lives somewhere with below replacement fertility—including the 3 billion in India and China—global growth after 2050 will be driven by a new set of countries, including those four in the chart above.

The news that China is depopulating and that India will assume the world’s top population spot within a few months is not really “news” at all—population pyramids let us see this coming. But a greater understanding of those two countries also helps us understand the tectonic forces shaping global population and how radical our demographic shifts are and will continue to be. India and China are so demographically dominant that trends involving their respective regions or income levels tend to be more about them as individual countries than reflective of their peer group as a whole. Together, they are so large that they even shape global trends. Only two countries out of 200-plus, India and China accounted for 35% of global population growth since 1950. When the world hits 9 billion in 2037, 1.6 billion of us will be Indian. As go China and India, so goes the world.

Before I close, I want to thank a reader who commented on a previous post that I wasn’t explaining “trends change” very well—you were right! That pushed me to look for a better way to explain. How’d this work?

·      Legal pathways can help reduce irregular migration: “The administration will give up to 30,000 people from the four countries the chance to enter the U.S. legally, but only if they don’t pass through Mexico and can meet other requirements. Since the new policy was announced, a senior Mexican official told me, the government has already noticed a drop in those migrants entering Mexico — and the United States.”

·      Yun Zhou argues that the problem of the low birth rate in China is being considered within existing unequal social structures and therefore measures to combat it do little to empower women and men to have children, so they don’t have them. Amen to that. And I would argue that China isn’t alone in that myopic approach. This kind of perspective is important to seriously consider if we want to understand the shift to super-low fertility (close to 1 child per woman on average), which is becoming more common.

·      It’s one thing to raise retirement age, it’s another to get older people to want to work, and it’s yet another thing to convince companies to hire older people. France, which has a higher proportion of retirees than does JAPAN(!!) is having a hard time getting employers on board, according to this NYT article.

8 Billion and Counting won an award! I do love my cover but Klosterman’s book takes the cake IMHO.