September 05, 2025
This chart tracks the UN’s latest demographic projections for four large populations: India, China, Europe, and the United States. Together, they account for about half of today’s world population.
The curves are shaped by what the UN expects to happen to future fertility, life expectancy, and migration worldwide.
India and China are the world’s most populous countries today, and the UN projects that both will remain at the top through the end of the century. Yet their trajectories diverge sharply in these projections.
China’s population has already begun to fall and is projected to more than halve to around 630 million by 2100. India, by contrast, is expected to keep growing for nearly four more decades, reaching about 1.7 billion people in 2060 and gradually declining to around 1.5 billion.
In contrast, the United States and Europe are projected to change more gradually. The US is expected to grow slowly and steadily, reaching about 420 million people by the end of the century. Europe’s population, meanwhile, is projected to decline. Based on these figures, its population peaked around 750 million in 2020, and is expected to fall to about 590 million by 2100, not far from China’s projected level.
The UN’s model is the most widely used baseline for international population comparisons, but all population projections are sensitive to the underlying assumptions. Other research groups use different demographic assumptions about fertility, life expectancy, and migration to reach different long-term population figures.
Explore the UN projections in our Population & Demography Explorer, or compare them with alternative scenarios in the Wittgenstein Centre Human Capital Data Explorer →
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Today
In the past, forests around the world were cut down on a massive scale. We lost some of the world’s richest ecosystems.
In recent decades, the picture has become more complex. Deforestation has not ended, but it is no longer happening everywhere. Since 1990, some regions have continued to lose large areas of forest, while others have slowed this long-run trend — and even reversed it.
The map shows regional changes in forest area based on the latest data from the Food and Agriculture Organization of the United Nations. Deforestation has been particularly large in South America and Africa. At the same time, the forested area has expanded in Europe, North and Central America, and large parts of Asia. These gains show that deforestation is not inevitable. When pressure on land falls, forests can return.
February 24
The Netherlands was the first country to legalize same-sex marriage in 2001. Since then, almost 40 other countries have followed suit.
You can see this in the chart, based on data from Pew Research. By 2025, same-sex marriage was legal in 39 countries.
Last year, two countries were added to the total. Thailand became the first country in Southeast Asia to legalize same-sex marriage, and a same-sex marriage bill also took effect in Liechtenstein.
February 21
The share of the world population living in extreme poverty has never declined as rapidly as in the past three decades.
The decline in China was particularly fast, and given that one in six people in the world lives there, we’re often asked whether the decline in global poverty was only due to the decline in China.
The chart shows the data that answers this question. In blue, we see the global decline. In red, we see the decline if we exclude China from the data. In the world outside of China, 33% lived in extreme poverty in 1990; by 2025, this share was down to 12%.
The large economic growth that lifted 940 million Chinese people out of extreme poverty since 1990 was a major contributor to the global decline in poverty. But the non-Chinese world also achieved a very large reduction.
It is not true that the global decline in poverty was only due to China. Extreme poverty has declined in China and the rest of the world.
February 19
Forty years ago in Japan, two babies were born for every person who died. Twenty years ago, these numbers were equal. And today, the ratio has reversed: one baby is born for every two people who die.
In the chart, you can see this change in the number of births and deaths over time.
Since deaths now greatly outnumber births, and because immigration is low, Japan’s population has started to shrink.
February 17
Debates over whether religion is booming or dying are common. What does the data say?
Most countries lack long-term data on religious identity, but results from the Pew Research Center offer insights into changes over the decade from 2010 to 2020. (Unfortunately, 2020 is the most recent year for which we have comparable global data.)
At a global level, there was barely any change. The share of people identifying with any religion dropped by just one percentage point, from 77% to 76%.
But religious affiliation did drop significantly across many countries in Europe, the Americas, and Oceania. You can see this drop for a selection of countries in the chart.
In Australia, rates dropped from 75% to 58%. In the United States and Chile, the percentage has decreased from roughly 85% to 70%.
So while religious affiliation is stable in many parts of the world, this data shows religion is becoming less prominent in others.
Note that this data is based on self-identification with any religion; it doesn’t tell us about changes in practices or rituals, such as prayer or attending services.
February 14
This chart shows one way to compare automated manufacturing across countries — it plots the number of robots per 1,000 manufacturing employees.
The chart shows very large differences between countries. South Korea stands out, with more than one robot for every ten manufacturing workers.
Singapore comes second, and China ranks third, close to Germany. The United States sits in the middle, close to the European average, below Switzerland, Denmark and Slovenia.
This perspective shows industrial robot adoption in relative terms. In another Data Insight, I looked at robot adoption in absolute terms. From that perspective, China stands out by a large margin: it’s a large economy with a huge manufacturing sector, and it has by far the largest stock of industrial robots.
Much of this expansion has happened recently: China’s annual installations increased 12-fold over a decade, helping it catch up to South Korea in terms of robots per worker.
February 12
Most people in the world are religious. When asked whether they identify with any religion, three-quarters of respondents choose one.
But in the chart, you can see huge differences in rates of religious affiliation across the world. In some countries, such as India and Pakistan, it’s almost universal: almost everyone identifies with a religion.
The opposite is true in China, where just one in ten people does. Several countries in East Asia, in particular, have particularly low rates of religious identification compared to other regions.
This doesn’t necessarily mean these populations hold no religious beliefs; they may still engage in activities that can be considered religious or spiritual, even though they don't describe themselves as belonging to any one in particular.
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