India, China, Europe, and the United States are on very different population paths

In 1970, Cyclone Bhola hit Bangladesh, killing more than 300,000 people. It was a strong cyclone, but not unprecedented. What made it so deadly was the lack of any early detection systems, alarms, or mass evacuation procedures. A huge storm surged into a densely populated area, and hundreds of thousands of people drowned in their homes.

Since then, Bangladesh has become much more resilient to these events. The chart shows the country's annual death toll from storms, stretching back to 1960.

Throughout the 1980s and early 1990s, a few large events claimed many lives. But in recent decades, the death toll has been low. That’s despite Bangladesh experiencing some extremely powerful cyclones. Cyclone Amphan (2020) and Mocha (2023) were both Category 5 — the strongest rating.

Bangladesh offers one of the clearest examples of how humans are not helpless in the face of “natural” disasters: investments in weather forecasting, early warning systems, and proper evacuation procedures can protect communities and save lives.

Electric cars have become incredibly popular in China. In 2020, one in eighteen new cars sold was electric. By 2024, this had increased to one in two.

This growth has pushed down sales of internal combustion engine (ICE) cars, which run mostly on petrol. As you can see in the chart, sales of ICE cars peaked in 2017 and have declined since.

The world reached peak ICE car sales just one year later.

The displacement of petrol cars with electric ones is vital in decarbonizing transport. The rise of electric vehicles in China means the IEA expects oil demand to peak earlier than previously projected.

Here, “electric cars” include fully battery-electric ones and plug-in hybrids. In China, 56% of them were fully battery-electric.

Those with access to electricity take many of its benefits for granted: food refrigeration reduces waste, the radio can keep us company during the day, and light at night makes it possible to study or get together after sunset.

According to data published by the World Bank, 30 years ago, only 5% of people in Kenya had access to basic electricity and its benefits.

Since then, the country has made substantial progress, as the chart shows: by 2023, 76% of Kenyans had access to a basic electricity supply.

Poor nutrition and illness can limit human growth, so long-term improvements in living conditions are often reflected in increases in average height.

At the individual level, height depends on many other factors, but genetics plays a particularly important role. Not all short people are undernourished or sick, and not all tall people are necessarily healthy. However, when we look at population averages across generations, broad patterns in nutrition and disease burden can play a visible role.

This is why historians often use height as an indirect measure of living conditions. By examining historical changes in height, researchers can gain insights into living standards during periods when little or no other data is available.

This chart presents estimates from Jörg Baten and Matthias Blum, published in the European Review of Economic History (2014). The lines show the average height of men by decade of birth in Denmark, the Netherlands, and Germany, from 1710 to 1980.

For the earlier period, the estimates are based mainly on military conscription records (which measured young men eligible for service), so they are not fully representative of the entire population.

These historical data points are less representative than modern survey data, but the changes are large enough that the overall pattern is meaningful even if exact levels carry some uncertainty.

The chart shows how rapidly average height rose in these countries during the 20th century, a trend consistent with major improvements in health and nutrition.

Guinea worm is an incredibly painful and debilitating disease; one that’s hard to imagine unless you’ve seen someone suffer from it.

As we explain in a dedicated article, it’s caused by the guinea worm parasite, whose larvae can be found in stagnant water. Drinking contaminated water lets the larvae enter the stomach and intestines. These grow into adult worms, getting into their joints and causing arthritic conditions, before emerging painfully through the skin.

The good news is that the world is extremely close to eradicating this disease. In 1989, more than 890,000 human cases were recorded globally, compared to only 15 in 2024.

As you can see in the map, these cases were recorded in just two countries: Chad and South Sudan.

There are three other countries — Ethiopia, Angola, and Mali — where guinea worm is still endemic (meaning it’s still considered present there), but they reported no new cases in 2024.

Here, we focus on guinea worm cases in humans, but it’s important to note that other animals — such as domestic dogs — can also be infected. This adds further challenges to eradicating the disease completely.

Large families used to be the norm in Colombia, but that has changed a lot over just a few generations. I come from Colombia, and my own family reflects this: my grandmother had eleven siblings, my mother had seven, and I have just one sister.

My family is one example of this broader shift within Colombia. In 1950, around the time my mother was born, the fertility rate was 6.4 births per woman. By 2023, it had fallen to 1.6.

That’s what the chart here shows. It plots the total fertility rate: the average number of children a woman would have over her lifetime, if she experienced the observed birth rates of women in her country in the corresponding year. It’s the most widely used measure to track birth patterns across countries and over time.

The chart shows that Colombia’s fertility rate is similar to that of richer countries like France and the UK. It also displays Colombia’s trend alongside China’s for comparison. Perhaps surprisingly, the slope (i.e., the speed) of Colombia’s drop has been similar to China's, despite the latter introducing a one-child policy.

Colombia’s experience mirrors a wider change across many middle-income countries, including much of Latin America. Education of women, urbanization, declining infant mortality, family planning, and changing norms are all key drivers of this trend.

If you ask people about whether the world as a whole is getting better or worse, most people say the latter. People are generally pessimistic about global or societal progress.

But they are typically much more optimistic about improvements in their own lives.

In the chart, you can see what share of people think they would be higher or lower on the “Cantril Ladder” five years in the future. The “Cantril Ladder” asks people to rate their lives on a scale from 0 (the worst possible life) to 10 (the best). Here, respondents were asked to rate where they are now, and where they think they’d be in five years.

As you can see, most people say they will be higher on the ladder across a wide range of countries. They expect their lives to improve.

Of course, this is not true of everyone, everywhere, but these results tend to support the argument that people are generally “individually optimistic, but societally pessimistic”.

Explore more data on happiness and life satisfaction across the world →