June 12, 2024
In the last two centuries, the price of lighting has decreased drastically.
You can see this in the chart, which plots historical data from Roger Fouquet and Peter Pearson. To allow for comparisons over time, the data is adjusted for inflation and expressed in prices for the year 2000.
In the 1300s, one million lumen-hours — a standard lighting measure — would have cost around £40,800 in 2000 prices. By 2006, this had fallen to £2.90, a 14,000-fold decline.
Innovations in lighting appliances, fuels, infrastructures, and institutions during the 19th and 20th centuries made this progress possible.
To put this in perspective, consider that a standard 100-watt incandescent light bulb today can emit about 1,700 lumens. Therefore, running one such bulb for 24 hours would produce about 50,000 lumen-hours. That means that 1 million lumen-hours today would require continuously keeping a standard 100-watt incandescent bulb on for about 25 days. Achieving the same amount of light with candles would require burning more than 100 candles every day for that period.
Most people today take the ability to switch on a light at night for granted. But those who live or have lived without artificial light can appreciate how important it is.
Today
Just a decade ago, almost three times as much electricity in the European Union was coming from fossil fuels as from solar and wind.
But last year, for the first time, solar and wind produced more than coal, gas, and oil combined. They accounted for just over 30% of total electricity production.
You can see this rise of solar and wind — and fossil fuels’ decline — in the chart.
This record happened despite a poor year for wind output due to low wind speeds and a slight increase in gas to compensate for lower hydropower output from dry conditions.
March 05
Marriage is closely linked to decisions about having children in many societies. It also matters for legal rights, family finances, and many other aspects of life.
The age at which people marry has rapidly changed in many countries. The chart shows this by tracking the average age at first marriage among women, using records from national statistics.
In Portugal, Italy, and Spain, the average age at first marriage has risen rapidly and consistently. Portugal saw the largest increase: from around 26 years in 2002 to over 32 years by 2020. This is more than six years in less than a generation. It’s also the largest increase among the countries in the OECD Family Database with data available from the early 2000s up to 2020 (the most recent year with available data in the series).
Changes in the timing of marriage have come together with other related shifts. For instance, a growing share of people are not marrying at all.
March 03
4,510 objects were launched into space in 2025, surpassing the previous peak of 2,903 objects in 2023 by a large margin.
The data shows that US agencies and companies were responsible for launching 3,708 of these objects — 82% of the global total.
The vast majority of these American launches consist of small satellites deployed as part of large commercial “constellations”. These interconnected networks of satellites now account for the bulk of all objects sent into orbit.
The rapid growth of satellite constellations makes it possible to expand Internet connectivity, but it also increases concerns regarding space debris and the congestion of Earth’s orbital environment.
February 28
In the 1970s, oil spills from tankers — container ships transporting oil — were common. Between 70 and 100 spills occurred per year. That’s one or two spills every week.
This number has fallen by more than 90% since then. In the last decade, no year has had more than ten oil spills, as shown in the chart.
The quantity of oil spilled from tankers has also fallen dramatically. Over the last decade, the average is less than 10,000 tonnes per year, compared to over 300,000 tonnes in the 1970s.
February 26
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.
