December 13, 2024
Demographic trends, such as births and deaths, can be influenced by many factors. Wars or pandemics can lead to higher death rates, while lower child mortality and access to contraception reduce the number of births.
But specific cultural beliefs can also have a strong effect, as in Japan in 1966. As you can see in the chart, the UN estimates that births decreased by about 20% from 1965 to 1966.
The reason behind this drop is unusual. Children born in 1966 had the “fire horse” as their birth sign. According to astrological predictions, women born that year would bring bad fortune, especially for their future husbands.
Families who either believed this, or wanted to avoid the risk of their daughters having difficulty in the marriage market, chose not to have children that year. Couples may have abstained or used contraception, and in addition, the induced abortion rate in 1966 was significantly higher than in the surrounding years.
The next year of the fire horse is 2026. With the decline of these beliefs in Japan, fewer arranged marriages (where the birth sign might be a significant factor), and generally declining birth rates, we are unlikely to see this sharp drop in births again.
Explore more data on births and fertility in our Population & Demography explorer →
Yesterday
Describing someone as “young” or “old” is rather arbitrary. However, something we can quantify is whether a given person is “young” or “old” compared to the rest of the world.
Imagine we sorted all 8 billion people alive today from youngest to oldest. The person standing right in the middle would be about 30 years old; that's the median age today. The chart shows the global median age and the UN’s projection to 2100.
In 2025, if you are over 30, you are older than most people in the world.
The chart also shows that if you were born in 1950, you stopped being “young” when you passed 20, as that was the median age in 1970.
As birth rates decline and life expectancy increases, the median age is expected to keep rising until the end of the century.
Whether you’re younger or older than most, the world is still relatively young, and this matters for many aspects of society, from the demand for resources and jobs to long-term planning for healthcare, education, and infrastructure.
If you want to dig deeper into this data, have a look at our Population & Demography Data Explorer →
April 21
Fifty years ago, almost half the adults in Great Britain smoked cigarettes, but this has become much less common.
In the 1970s, half of men and 40% of women over the age of 16 reported smoking cigarettes. Since then, smoking rates have steadily fallen. By 2023, this was just 12% of men and 10% of women.
This dramatic decline is the result of decades of public health efforts such as clear warnings on cigarette packs, bans on tobacco advertising, indoor smoking restrictions, and support to help people quit. Newer technologies — including vaping products, nicotine patches, and medications — have also helped many people quit.
Despite this, smoking remains the leading risk factor for preventable death in the UK, raising the risk of many cancers, heart attacks, and strokes. Fewer smokers means fewer people suffering from these serious diseases.
Read more about the global problem of smoking in an article by my colleague Max →
April 18
A recent report by the Inter-American Development Bank (IDB) highlights the high concentration of poverty in Latin America. Across the region, around 89 million people — more than one in seven — live on less than $3.65 a day.
Poverty can be measured using various poverty lines; here, we’re looking at the $3.65 line, which the World Bank uses to define poverty in lower-middle-income countries.
The chart shows that 52.2 million people living under this line are in just three countries — Brazil, Venezuela, and Mexico — representing 59% of the region’s total.
As the report explains, while Brazil and Mexico don’t have the highest poverty rates, their large populations mean they have the largest number of people living below this line. Venezuela, in contrast, has a smaller population but one of the region’s highest poverty rates.
Identifying where poverty is most concentrated can help target efforts to reduce and eliminate it.
You can explore more data on poverty, including different poverty lines and world regions, in our Poverty Data Explorer →
April 16
One of the most pressing problems I hear from European friends is that they cannot find an affordable place to live. Housing costs represent one of the largest expenses for most Europeans. While many people rent, purchasing a home remains a goal for some.
The chart shows the change in house prices of residential properties purchased by households in 12 countries across the European Union since 2010. In many, prices have increased sharply (even after inflation). Portugal shows the most dramatic increase, with prices rising by 50%.
But this large increase has not happened everywhere. Rises have been more modest in France and Belgium, and prices have actually fallen considerably in Romania and Italy.
These huge differences matter to young Europeans hoping to find their first home after leaving their family house.
April 14
It’s often difficult to understand the scale of wildfires globally. That’s because most news coverage focuses on only a few countries.
News headlines might be filled with stories about large fires in Greece, Portugal, the United States, or Canada, but when we look at the data, the global total is no higher than usual.
This is because the global trend is so strongly dictated by the extent of fires in Africa, which we almost never hear about. As you can see in the chart, Africa experiences more than half of the burned area globally every year. In some years, it’s as much as two-thirds of the total.
Whether it’s a “high” or “low” year for wildfires globally largely reflects whether it’s a high or low year for Africa. These global trends don’t tell us much about the extent of wildfires in other regions.
Track global, regional, and country-level data on wildfires, which we update weekly →
April 11
Global air travel collapsed in 2020 as lockdowns and travel restrictions took effect. With fewer flights, CO₂ emissions from commercial aviation fell sharply. The chart shows Egypt as an example, where they dropped by more than half.
As air travel rebounded, emissions rose too — in many countries, they’ve now surpassed pre-pandemic levels. These countries are highlighted in red on the chart.
Emissions from flying make up about 2.5% of global CO₂ emissions, but air travel has one of the highest carbon footprints per passenger. As demand grows, reducing its impact will be important for meeting climate goals.
Read my colleague Hannah Ritchie’s article to learn more about aviation’s contribution to global CO₂ emissions →
April 10
The peak flowering of cherry trees in Kyoto, Japan, has been recorded since the ninth century. Yasuyuki Aono and colleagues from the Osaka Prefecture University collated this data from historical diaries and chronicles, indicating the dates on which cherry blossom viewing parties had been held or other observations of peak blossom.
In 2025, the peak cherry blossom happened on April 4th.
This long-run data is a proxy measure for how the climate has changed. The onset of cherry blossoms is linked with warmer temperatures. Since the early 20th century, the combined effects of urbanization and higher temperatures due to climate change have gradually moved the peak blossom earlier in the year.
Explore this data in our interactive visualization →
