Our World in Data

Almost all the growth in global coal use since the late 1980s has come from China. Outside China, the world’s use of coal has barely changed since the late 1980s. It was just over 20,000 terawatt-hours back then, and almost four decades later, it is still the same. But the change has been very different in China. The country has increased the use of coal enormously, and today, China is burning more coal than the rest of the world combined. The future of global coal use, and the emissions that come with it, depends heavily on what happens in China. (written by @MaxCRoser)

Much of the economic data we use to understand the world, such as the incomes people receive, is recorded in the local currencies of each country. On their own, numbers in local currencies tell us nothing about how they compare. One obvious approach would be to convert them into a common currency using market exchange rates. But this doesn’t give us the comparison we often look for: what money can actually buy in different countries. This is because the cost of living varies a lot across countries. International dollars are a hypothetical currency that aims to have the same purchasing power everywhere. They are adjusted for differences in living costs across countries and price changes over time. Wherever it is “spent”, one international dollar buys the same goods and services as one US dollar would in the United States. Making incomes comparable across countries matters especially for our understanding of global inequality. Using market dollars — local currencies converted to US dollars using market exchange rates — to compare incomes across countries understates people’s real income in countries where local prices are often much lower than in the US. Take India, for example. Its gross domestic product (GDP) per capita is almost 30 times lower than that of the US in market dollars. But when we adjust for differences in living costs, the gap shrinks to about eight times lower. For Burkina Faso, the difference is even starker: its GDP per capita is 83 times lower than that of the US in market dollars, and 30 times lower after adjusting for differences in living costs. Global inequality remains large, even after accounting for what people can buy locally.

Population aging is pushing up Chile’s crude cancer death rate, even as age-adjusted rates are falling. In Chile, the annual number of cancer deaths as a share of the total population has been rising for decades. From this, it would be easy to assume that cancer is getting worse. But the chances of dying from cancer at most ages are lower than they used to be. The missing piece is that the country’s population is changing quickly, and older people now make up a much larger share. That’s what the chart shows. The crude cancer death rate, in red, counts registered cancer deaths per 100,000 people of all ages. This metric has been going up, reflecting the fact that cancer risks increase steeply with age, and the population has grown much older. The blue line, by contrast, shows the age-adjusted rate. This metric removes the effect of aging by holding the age structure constant. This line has been falling for decades, which means that Chileans at almost every age are now less likely to die from cancer than people of the same age were in the past. The pattern we see in Chile is happening in many other countries, too, and is visible in the global estimates. (written by @EOrtizOspina)

Which vaccines do children around the world receive? Every year, the World Health Organization (WHO) and UNICEF estimate what share of children in each country get each routine vaccine. Their Estimates of National Immunization Coverage cover vaccines against 13 diseases, from measles to rotavirus, in 195 countries since 1980. They start from the doses that health services report and check them against household surveys. For the small share of countries that haven’t reported any data for the most recent year, WHO and UNICEF estimate coverage from the years before. The chart shown here is about the vaccine against human papillomavirus (HPV), which causes nearly all cervical cancers. It shows the share of girls who had their last dose between the ages of 9 and 14, measured when they turn 15. Coverage varies a lot from country to country, even within the same world region. We recently updated our charts with the July 2026 release, which adds 2025 estimates for every country. For HPV, we now have data for 160 countries and territories in 2025, compared with 146 a year earlier. (This data update was led by Tuna Acisu.)

Solar and wind power have grown quickly in Poland, but coal still dominates. The share of electricity produced by solar and wind in Poland more than doubled in just four years. In 2021, these renewable sources produced just 11% of its power; by 2025, this had risen to 25%. You can see this growth in the chart, based on electricity data from Ember. Solar and wind output, combined, grew very little in 2025, due to weak wind conditions. Solar output continued to grow, but it was barely enough to offset the decline in wind power. Poland still has one of the most coal-intensive electricity mixes in Europe, with coal producing 50% of its power. The country has committed to moving away from it in the next few decades; growth in solar and wind generation will play a key role in this. (written by @_HannahRitchie and @parriagadap)

📝 New article on Our World in Data: Around half of people will experience a mental health issue in their lifetime. How many people struggle with mental health issues? International and national health statistics will often give us estimates for how many people have depression, anxiety, or an eating disorder at any given time. But people can develop mental health disorders at any point in their lives, or experience recurring episodes over many years. What share of people will ever experience one? A study by John McGrath and colleagues tries to answer this question by drawing on data from 29 countries and over 150,000 people across the world. By interviewing people at different stages of life, they can build up an understanding of how this risk accumulates over an individual’s life course. They estimate that roughly half of the population will experience one of 13 common mental health disorders by the time they reach 75. Depression is the most common; by the age of 75, one in three women has experienced depression at some point in their lives. One in five men has. For anxiety, the share is similar, as is the gender gap. For substance use disorders, it’s the opposite. In this article, we look at these estimates in more detail and discuss why the true share might be even higher.

One in four people in the world is younger than 15. Just one in ten is 65 or older. But there are huge differences in this distribution across countries. In the chart, we’ve shown these global figures alongside the country with the largest share of children, the Central African Republic, and the one with the largest share of older people, Japan. In the Central African Republic, half of the population is under 15. Being over 65 is pretty rare: just 2% of the population. Japan is the opposite. Being a child or adolescent puts you in the minority. Almost one-third of the population is 65 and older, and that share is growing quickly. These differences in age distribution matter a lot for a country’s infrastructure, socioeconomic conditions, and public spending — from pensions and healthcare to childcare and education. (written by @_HannahRitchie)

Every year, over half a million women develop cervical cancer, and more than 300,000 die from the disease. These deaths are particularly tragic because we can prevent them through vaccination and early screening. Because cervical cancer is caused by a virus — the “human papillomavirus” (HPV) — it can be prevented through vaccination. HPV vaccines are highly effective, as demonstrated in large-scale randomized controlled trials. Research shows that, if given early, vaccination reduces the risk of serious cervical cell changes by 99% for the HPV types most likely to cause cervical cancer. In England, younger cohorts vaccinated at school show dramatically lower rates of cervical cancer than older cohorts when they reach the same age. In the youngest cohort, which had a vaccination rate of 89%, cervical cancer rates were around 87% lower than in the oldest cohort. Yet HPV vaccination rates are low, or vaccines are unavailable in many countries. In many countries across Africa and Asia, HPV vaccines are not offered routinely at no cost at a national level. Higher vaccination rates could prevent hundreds of thousands of cervical cancer cases every year. Researchers Kate T. Simms and colleagues estimate that 80% to 100% vaccination rates for both boys and girls, with catch-up vaccinations for adults, could prevent nearly 50 million cervical cancer cases by 2100. By investing in vaccination and screening, the world could save hundreds of thousands of lives each year, prevent avoidable suffering, and make cervical cancer a disease of the past.

How is life at different levels of GDP per capita? The chart shows the relationship between GDP (gross domestic product) per capita — a measure of average incomes in a country — and people’s living conditions. Where GDP per capita is higher, living conditions are far better in many ways. Where average incomes are higher, children die less often, fewer of them are born dead, mothers die less often, fewer children suffer from hunger, doctors can focus on fewer patients, people live longer, more people can read, children have better access to education and better learning outcomes, more people have access to electricity and clean drinking water, and people are happier with their lives. The disparity between countries with a low and a high GDP per capita is enormous. Looking at the first panel, for example, you can see that a child born in one of the poorest countries is more than 20 times as likely to die as a child born in one of the richest. (written by @MaxCRoser)

Tracking who trades with whom around the world. The International Trade in Goods dataset from the International Monetary Fund (IMF) records how much each country exports to and imports from each of its trading partners. This data goes back to 1948. Countries report to the IMF based on their own trade records and statistics. If this data isn’t enough, the IMF uses the country’s trading partners’ records instead. This map shows, for each country in the world, the country from which it imported the most goods in 2025. For 83 of the 209 countries with data, that was China — this includes most of Asia, more than half of Africa, and most of South America. (Countries whose largest partner is not one of the most common ones are shown as “Other”.) We recently updated eight of our charts with the IMF’s latest release, which adds data for 2025 for 209 countries and territories. (This data update was led by @parriagadap.)