July 28, 2025
Economic growth is easy to understand: it means that people have access to goods and services of increasing quantity and quality.
What is hard, however, is to measure economic growth. This chart shows two ways of doing this for US growth over the past 160 years.
The purple lines represent a straightforward approach: each line tracks the share of households with access to one specific good or service. Starting from the top, you see the rising provision of basic infrastructure like running water, flush toilets, and electric power. You can also see the increasing availability of communication technology: radios, TVs, the Internet, and mobile phones. And further down, you see the rise of technologies that reduced work at home: vacuum cleaners, washing machines, dryers, and dishwashers.
This approach is very concrete; it shows practical ways in which the production and consumption of specific goods increased over time. The downside is that it only captures a limited number of particular goods. Millions of goods and services are produced and consumed, and most are not recorded with such precision.
A way to measure how people’s access to the full range of goods and services changes is to measure people’s incomes. This way of measuring growth is shown in the top left panel. The data on average income, here measured by GDP per capita, tells us that the average American was 13 times poorer in 1860 than in 2022 (adjusted for inflation).
These two ways of measuring economic growth have pros and cons: one is concrete but not comprehensive, the other is comprehensive but quite abstract. If we want to understand what growth means for our societies, I find it helpful to combine them both.
Today
In every region of Africa, hunger is more prevalent than a decade ago.
The chart shows the increase in the share of the population that is undernourished, comparing 2014 and 2024 (the most recent year available). These estimates come from the Food and Agriculture Organization of the United Nations.
The situation across Africa is dire. In Middle Africa, where hunger is most acute, almost 1 in 3 people are undernourished. In Eastern Africa, the figure is roughly 1 in 4. Across Africa as a whole, it's 1 in 5.
This marks a reversal of a longer positive trend: over the preceding decades, hunger had been falling across much of the world, including parts of Africa. That progress has now stalled or gone into reverse. Conflict, extreme weather, and the economic disruption of the COVID-19 pandemic have all contributed.
April 11
The concept of “leapfrogging” is popular in development. It suggests that, as they develop, lower-income countries can skip intermediate technologies or systems and go straight to the modern equivalent.
One example of this is the use of landlines and mobile phones.
The landline telephone was invented in 1876 and became a dominant form of communication across Europe and North America. As you can see in the chart, it was increasingly adopted in the United States and the United Kingdom throughout the 20th century.
However, mobile phone adoption increased rapidly in the 1990s, and landlines have declined since the millennium. Mobile phones have become a substitute.
But many countries have almost skipped landline adoption entirely. Ghana and Nigeria are good examples: landline subscriptions have remained extremely low, and instead, mobile phone adoption has exploded.
April 9
Even after years of working with global health data, one statistic that I’m always struck by is the number of people who die by suicide every year. In 2023, it was estimated to be around three-quarters of a million.
That means suicides account for more than 1 in every 100 deaths in the world.
But a world where so many die from suicide is not inevitable. We know this because global suicide rates have fallen by an estimated 40% since the 1990s.
You can see this in the chart: rates have fallen from 15 to 9 deaths per 100,000 people over the last thirty years.
The large differences between countries also suggest that there are things that can be done to reduce this number even further.
April 7
Some technologies central to the clean energy transition depend on rare earth elements. The permanent magnets found in many electric vehicle motors and wind turbine generators rely on them. They are also used in some military hardware.
China dominates global production of rare earths; in 2024, it accounted for nearly 70% of the global total.
But the picture is not as concentrated when you examine which countries have rare-earth reserves. That is what the chart shows, plotting production and reserve shares side by side. China still holds the most known reserves, but at 49%, this is substantially lower than its production share.
Brazil holds 23% of reserves and is barely mining them. India, Vietnam, and Russia also hold significant reserves, but only a small fraction of current output.
The large gap between where reserves are located and where mining occurs partly reflects China's early investment in mining infrastructure and processing capacity, which other producers have not yet matched. Other countries hold the geological potential but have not yet developed the infrastructure to convert it into production at scale.
April 4
Child mortality rates in China have fallen from more than 20% in 1950 to less than 1% today.
But this steady progress was interrupted in the late 1950s during the “Great Leap Forward”. This was China’s national plan to industrialize rapidly, but it resulted in widespread famine and economic turmoil.
As the chart shows, child mortality rates spiked in China over this period, with up to one in three children dying before reaching the age of five. This change was so dramatic that it is also clearly visible in the global trend.
This data comes from the UN’s World Population Prospects.
April 2
Around 4 in 10 women worldwide live in countries where abortion is illegal or highly restricted. But these bans do not stop abortions completely; many women still get them, but in unsafe and unsanitary conditions.
A study published in The Lancet estimated that 45% of abortions globally are unsafe. In some regions, the share is estimated to be around three-quarters. You can see this in the chart.
This data is around ten years old, but represents the latest estimates available (suggesting that this topic gets very little attention).
Unsafe abortions dramatically increase the health risks for women. Safe abortions have very low mortality rates, typically below 1 death per 100,000 abortions.
In regions where the majority of abortions are unsafe, mortality rates can be several hundred times higher; in Western and Middle Africa, around 1 in 200 abortions result in the woman dying.
It’s estimated that approximately 8% of maternal deaths in the world are caused by unsafe abortions. That’s 23,000 women every year.
March 31
Depression, anxiety, and other mental health problems are common everywhere. They are not confined to any particular income level.
But access to care is rare. In much of the world, people who struggle with their mental health have almost no psychologists or psychiatrists to turn to.
Mental health care is scarce in all places, but it is much scarcer in poor countries. Governments in high-income countries spend about $66 per person per year on mental health care, as the chart shows. In low-income countries, that figure is $0.04.
This gap in spending reflects a gap in people. As the WHO’s latest Mental Health Atlas highlights, there is roughly one psychiatrist per million people in low-income countries. High-income countries have 70 times more.
A recent study in the Lancet Psychiatry estimated that globally, only 9% of people with major depressive disorder receive a “minimally adequate treatment”. In high-income countries, it is 27%; in Sub-Saharan Africa, just 2%.
Hundreds of millions of people in poorer countries live with treatable conditions and have no access to a psychologist or psychiatrist. It is one of the largest gaps in global health — and one that receives remarkably little attention or funding.
There are efforts to close this gap without waiting for the workforce to catch up. One approach is to train lay counsellors — people without formal clinical qualifications who learn to provide psychological support. Randomized trials in India and Zimbabwe have shown this can be effective for depression.
Another approach is to use technology: apps and, increasingly, AI-based tools that can extend the reach of limited clinical expertise. These are not substitutes for a functioning mental health system, but in places where that system barely exists, they offer a starting point.
