Which countries have fertility rates above or below the “replacement level”?

When I was born in the 1990s, the average carbon dioxide (CO2) emissions in the United Kingdom were about six times higher than in China, but these trends have converged in my lifetime.

You can see this in the chart: in 2022, China’s per capita emissions matched those in the UK.

Once a country that ran on coal, the UK has closed its last coal plant. This has been the main driver of its emissions decline.

Meanwhile, rapid economic growth, powered mainly by coal, has ramped up emissions in China.

These emission numbers are adjusted for trade. Based on domestic production, China’s per capita emissions are much higher than the UK's. But since China is a net exporter of goods (and emissions) and the UK is a net importer, the gap closes when we adjust for consumption.

These emissions are based on domestic consumption and do not include international aviation or shipping, where Brits are likely to emit more.

There are many ways to compare national contributions to climate change; explore them here →

Smokers are about 21 times more likely to die from lung cancer than people who never smoked, and they face increased risks from over a dozen other diseases. I know people who died from smoking: you probably do too.

In 2008, the World Health Organization created a set of tobacco control policies with different tiers, the highest of which are considered “best practices” — they are listed on the chart.

The chart also shows the share of the global population living in countries that had enacted these policies as of 2007 and 2024.

What surprised me is how recent most of these policies still are. In 2007, only a tiny share of the global population benefited from these policies. Since then, coverage has increased across all these measures, but most of them still reach less than half of the world's population.

What is the share of taxes on the retail price of a pack of cigarettes? See the data for each country →

For most of history, almost everyone everywhere was very poor. Hunger was common, half of the children died, and, as the chart shows, average incomes were low across all regions.

The chart also shows how people’s incomes have changed over the last two centuries. The chart highlights a stark divergence: while average incomes in every region have increased, the pace of this growth has varied enormously. Western Europe and the “Western Offshoots” (like the US and Australia) experienced early and sustained economic growth. Meanwhile, Sub-Saharan Africa and South Asia grew much more slowly.

Two hundred years ago, people in all regions were similarly poor. Today, the average incomes of people in Australia, the US, or Denmark are more than 15 times higher than those in Sub-Saharan Africa.

I wrote an article on how economic growth is possible and why it is important: “What is economic growth?” →

Norway is leading the way in the transition from petrol to electric cars. Almost every new car sold in Norway is electric. Hardly anyone buys a combustion engine car anymore.

However, data on new car sales doesn’t tell us about the distribution of cars on the road. There is a lag between sales and stocks, because people can hold on to their existing petrol and diesel cars for as much as a decade or more.

But after years of electric cars dominating the market, one-third of cars in use in Norway are now electric. The chart shows this growth.

The share was only 12% five years earlier, which shows that this transition can happen relatively quickly.

As the global leader, Norway’s experiences can help to inform other countries on factors like charging networks, grid management, and the impacts of electric car uptake on emissions and air quality.

See how common electric cars are in other countries across the world →

The Agricultural Revolution — the transition from hunting and gathering to farming — didn’t end hunger. That’s because more food didn’t mean more per person: it meant more people.

The English cleric Thomas Malthus predicted this would continue forever: food production would always be outpaced by population growth, making lasting progress against hunger impossible.

But at least since the mid-20th century, England has left mass hunger behind. How was this possible? How did English farmers prove Malthus wrong?

The chart shows one central part of the answer. For centuries, cereal yields in England — for staples like wheat and barley — were stuck at about 0.6 tonnes per hectare. That means farmers needed a plot of 100 meters by 100 meters to grow 600 kilograms of cereals per year. Hunger was widespread.

But this changed from the 17th century onward, accelerating a hundred years ago. In a dramatic transformation known as the Second Agricultural Revolution, farmers found ways to grow much more food on the same land.

Today, after four centuries of rising productivity, English farmers are growing about ten times more food on the same land than in the past. This has made it possible to increase food production faster than population growth, breaking England out of the “Malthusian Trap”.

The chart also shows that the world as a whole is changing in the same direction. Global average yields have tripled in the last six decades. Today, yields are already about five times higher than in England in the past. If yields continue to follow this trajectory, it would bring us much closer to the end of global hunger, while also sparing land for nature.

My colleague Hannah Ritchie wrote about how climate change might affect crop yields in the future →

It’s hard to imagine many things that are more terrifying than your baby contracting HIV. This is the reality for around 130,000 families every year.

Just a few decades ago, this figure was over half a million. Most of these infections were passed on from mothers who had HIV themselves.

But the introduction of anti-retroviral (ART) drugs and other interventions has meant that most infections can be prevented. If the mother takes ART during pregnancy, it dramatically reduces the risk of passing on HIV. In some cases, giving ART to the baby in the first few weeks of life can help too.

In the chart, you can see this decline in new HIV infections in children. On top, you can see the huge number of cases estimated to have been averted thanks to these interventions; they amount to almost a quarter of a million cases every year.

Explore more of our work on HIV/AIDS in adults and children →

Global trade has never been a bigger slice of the world economy. However, China, the country that most people think of as the export giant, has seen a decline in its trade-to-GDP ratio in the last 15 years.

The chart shows China’s trade in goods and services as a share of its Gross Domestic Product (GDP). In 1970, it was just 5%. Following Deng Xiaoping's economic reforms, which opened China to market forces and international trade, this figure soared to 64% in 2006. But since then, it has fallen considerably, reaching 37% in 2023. China's exports have grown in dollar terms, but its economy has expanded even faster, making trade a shrinking share of the whole.

While the 2008 financial crisis disrupted global trade, China’s trajectory also reflects the increase in domestic demand for its production. For years, Chinese officials have advocated rebalancing the economy away from export dependence and toward one driven by domestic consumption. A rising middle class now buys more of what China produces, reducing its reliance on international markets.

Explore more data on our Trade and Globalization page →