Under-5 child mortality has been cut in half since 2000, UNICEF reports

The United Nations Children's Fund works globally to protect children's rights and well-being. Its 2024 report on child mortality reveals that under-5 deaths have halved since 2000. The report includes interactive data visualizations that can be sorted by year or topic.

Global life expectancy has more than doubled since the 1850s

The human species experienced a dramatic increase in expected lifespan over the past 150 years. Antibiotics, improved sanitation, and better worldwide food distribution are a few factors contributing to this rapid transformation. Use this interactive resource to explore longevity gains over time and compare these improvements across the globe.

Becoming a man in ancient Rome

In ancient Rome, boys between the ages of 14 and 17 underwent a traditional ceremony marking their transition from childhood to adulthood. This article explores what we know about this common practice and its significance. Learn about the ritual celebration, which included a new white toga, sacrifices, and becoming registered as a citizen.

Measuring the chance a Roman emperor would die violently

The odds of survival for a Roman emperor were like playing Russian roulette with a six-chambered revolver and four bullets, according to this scientific journal article. Of the 69 rulers of the unified Roman Empire between 14 CE and 395 CE, 43 suffered a violent death. This journal article examines Roman emperors' time-to-violent death using statistical tools of survival data analysis.

The disparity in life expectancy between wealthy and impoverished nations has notably narrowed

In 1950, people in Norway lived to age 72, on average, while those in Mali lived to just 26. By 2015, the countries with the worst conditions had made such significant progress that the global average life expectancy had surpassed the rate of any nation in 1950.

Ancient Rome explained

Ancient Rome left a high water mark on ancient civilization with its pragmatism and administrative prowess, dominating through its efficient military, engineering, and administration. At least 50 million people—a quarter of the world population—inhabited the empire, covering 5 million square miles at its height.

Explore US public health data

This resource tracks key US health metrics, including mortality causes, child survival rates, and life expectancy comparisons, to inform future health improvements, with regularly updated global estimates.

Penicillin ended scarlet fever’s deadly threat to children

Between 1840 and 1883, scarlet fever was among the leading causes of childhood death in the United States, with case fatality rates ranging from 15% to 30%. Today, thanks to antibiotics like penicillin, the mortality rate is below 1%.

Mortality tables help determine the probability of death for specific populations

A mortality table is a diagram that helps predict a specific population’s likelihood of death within a particular time period. Life insurance companies often use them to help figure out pricing for their insurance products. They’re sometimes known as actuarial tables or life tables.

Diphtheria was once a leading childhood killer before antibiotics and vaccines

In 18th- and 19th-century outbreaks, some New England families lost as many as eight children to diphtheria, and fatality rates in hospitals often topped 60%. The invention of antitoxins, penicillin, and vaccines dramatically reduced deaths.

Marriage rates are declining, especially in the richest countries

89% of the world’s population now live in countries with falling rates. Increasing costs of living, the financial burden of starting a family, and the rise of secularism are some of the key factors reducing marriage rates among the less affluent.

In the US, 3.6 million babies were born in 2023

That year, about 40% of the babies were born to unmarried parents, and about 32% of the births were born via cesarean. On average, mothers were 27.5 years old when they had their first child.

Obesity rates have more than doubled worldwide since 1990

In the US alone, the percentage of the population meeting the clinical standard of obesity rose from less than 20% to more than 40% over the past three decades. This rise has been matched by many countries across the globe, from industrialized to developing nations.

An analysis of ancient texts found that dementia was rare in ancient Greece.

US cancer mortality rates have been falling for 25 years

The American Cancer Society's "Cancer Facts & Figures 2025" report provides comprehensive statistics on cancer incidence, mortality, and survival rates in the United States. Cancer rates in the US continued a long-running downward trend, driven primarily by a steep drop in lung cancers (mostly from a decrease in habitual smoking) and better preventative monitoring. This site leads to incredibly in-depth reports and slides on the current state of the fight against cancer.

France once had a reproduction czar to help midwives deliver babies

Much ado is made about falling marriage and birth rates worldwide, and how they might affect tax bases, retirement funds, and social standing. But this isn’t the first time marriage, and subsequently reproduction, have fallen out of favor. Some countries have resorted to drastic measures to restore the tarnished state of these hallowed institutions.

Play 17th-century death roulette

Before modern science and medicine, death was much harder to escape. Using real mortality records from London's Dreadful Visitation–a collection of all the Bills of Mortality from 1665–this interactive game gives you an idea of what may have possibly killed you during the Great Plague. Grow your appreciation for life today as you stumble upon causes of death like “livergrown” and “drowned at St. Katharine’s by the Tower”.

The US trails behind other developed countries in reducing its stillbirth rates and may learn from Australia

Australia is in the vanguard of efforts to bring down stillbirth numbers with a national stillbirth plan integrated into its healthcare system, supported by clinicians, nurses, midwives, and politicians. Its work also includes a public awareness campaign, more regular fetal monitoring and follow-up for potential interventions, and more maternal advice about care and safety during pregnancy.

Understanding the global crash in fertility rates

This article breaks down the global crash in fertility rates. According to researchers, a global crash in children being born will have a “jaw-dropping” impact on societies. Women are choosing to have fewer children as a result of more women in...

Visualizing cause of death over time in America

As people age, their life expectancy decreases, but the timing and speed of this decline have evolved over the years. Check out this chart which shows the shift in various causes of death of Americans over the last few decades. Data from the...

Global population growth peaked six decades ago, at 2.3%.

The ancient Egyptians developed the first pregnancy test—and scientists tested it in the 1960s and discovered it was accurate about 70% of the time.

Roughly 10% of the world's population is older than 65 (2023 data)

With recent advances in medicine, sanitation, and nutrition, expected lifespans have rapidly risen around the globe—resulting in a rapidly aging global population. The worldwide distribution has seen a nearly 600% jump in the population of people aged 65 and older.

The measles vaccine has saved an estimated 94 million lives since its introduction.

Estimate the costs of an ancient Roman vacation

Death taxes have helped fund wars since the 1860s

Death taxes date back to 700 BCE and were used in Ancient Rome and Ancient Egypt. In the US, they've been used to finance wars since the Civil War, and have been levied on both the estate and beneficiary. The estate tax created during WWI to help finance war efforts is still in effect today.

Why do humans have such long childhoods?

Humans have over twice as long childhoods than other animals with similar lifespans like whales and elephants. A human child can grow for nearly 20 years before they become a reproducing adult. Researchers believe there's a connection between long childhoods and human's unusually large brain size, though the science is not totally clear. Dive into what scientists know here.

‘Roman military pensions’ were among the first known pensions in history

Instituted by the first Roman emperor, Augustus, around 13 BCE, these early iterations of pensions made it so soldiers sometimes received about a decade's worth of their pay, plus some land to live on. Augustus instituted these pensions to secure loyalty and reduce the risk of coups and unrest. This video includes more fun tidbits about the history of retirement.

The concept of life insurance likely originated in ancient Rome around the year 100 BCE

However, life insurance policies didn’t reach the Americas until 1759, when life insurance started being used to protect the families of Protestant ministers when said ministers died. This timeline of life insurance’s early history—and how it has evolved since then—provides more details.

Data visualizations showing population growth around the world

This page presents data, charts, and analysis on changes in population growth around the world. Over the last few centuries, the human population has gone through an extraordinary change. In 1800, there were 1 billion people; today, there are more...

Heat-related deaths may have climbed by more than 50% over 20 years

Between 2000 and 2009 one study suggests annual heat deaths averaged around 2,670, but between 2010 and 2020 that figure was likely more than 4,000. Researchers studied 54 million death records from the contiguous US and created mathematical models to arrive at these figures, noting that a combination of aging populations and climate change drove that increase.

In the original 2004 blue zones study, which sought to verify the ages of long-lived, healthy populations in Sardinia, Italy, researchers hypothesized that inbreeding in these isolated communities may have helped promote their longevity.

Twelve centuries of Roman history in 20 minutes

The Roman Empire may have been the world's first example of globalization, covering thousands of miles and crossing language barriers armed with Latin and short swords. Its legacy is nearly unparalleled in contemporary Europe, with nearly 50 Romance languages deriving from Latin.

Triplet birth numbers are dropping—and that may be a good thing

Pregnancies involving three kids or more have dropped 62% from 1998 to 2023, a trend that the Centers for Disease Control and Prevention links to fewer embryo transfers during assisted reproduction procedures—a transition prompted by more refined techniques and technical advances. Though multiple births can occur naturally, often pregnancies involving multiple births have been the result of efforts to ensure pregnancy success by transferring multiple embryos.

Why humans evolved single-child pregnancies

While birthing twins has been a rare occurrence for humans, research suggests that twins were actually the norm much further back in primate evolution. It’s proposed that single-childbearing turned out to be critical for the evolution of larger babies with larger heads. Discover more about the shift that gives insight into primate evolution.

What happened to thousands of teens from the 1990s?

Scientists followed thousands of teenagers from 1997 into their 30s, cataloging their adverse experiences along the way via nearly three decades of interviews. Teens who grew up dealing with poverty, uninvolved parents, and other childhood stressors and traumas racked up an ACE score. These adverse childhood experiences have lifelong impacts on one's health, relationships, financial security, and "pretty much everything else," making them more likely to suffer premature death.

As of 2022, scientists estimate that 117 billion people have been born on Earth

Although no demographic data exist for more than 99% of the time humans have existed, this value can be estimated by tracking approximate population sizes over different periods and the birth rates within those periods. In 2022, about 6.8% of humans that have ever been born were alive.