Picture the world in 1925. Not the jazz clubs or the flappers. The data. One in four children born that year would die before their fifth birthday. Three out of four people lived in what we'd now call extreme poverty. The majority of humans on Earth couldn't read.
One hundred years later, every single one of those numbers has been transformed. Not improved. Transformed. The scale of change is so large it's hard to put into words. So let's just let the data do the talking.
The Scorecard: Then vs. Now
| Metric | 1925 | 2025 | Change |
|---|---|---|---|
| Global life expectancy at birth | ~34 years | ~73 years | +39 years (+115%) |
| Child mortality (under-5 deaths per 1,000 births) | ~250 (25%) | ~37 (3.7%) | Down 85% |
| Extreme poverty rate (below ~$2.15/day, 2017 PPP) | ~75% | ~9% | Down 66 pp |
| Global adult literacy rate | ~27% | ~87% | Up 60 pp |
| Democracies worldwide | ~25 | ~90 | Up 3.6x |
| Maternal mortality (per 100,000 live births) | ~600-800 | ~197 | Down ~70% |
| People with access to electricity | <5% | ~91% | Up 86 pp |
| Global average years of schooling | ~2 years | ~8.5 years | Up 4x |
| Smallpox deaths per year | ~1-2 million | 0 | Eradicated |
Sources: Our World in Data (Gapminder), World Bank World Development Indicators, UN Population Division, WHO, UNESCO. Historical 1925 estimates are necessarily approximate. But the magnitude of change is not in serious dispute.
Life Expectancy: The Number That Says Everything
In 1925, average global life expectancy was around 34 years. Today it's about 73. That's nearly a doubling of the average human lifespan in a single century.
And here's the thing: people in 1925 didn't age faster. The revolution wasn't in getting old gracefully. It was in keeping people alive through the early years. Vaccines, antibiotics, clean water, basic sanitation. If you made it to 40 in 1925, your remaining life expectancy wasn't dramatically different from today. The war was won in infancy and childhood.
In 1925, roughly 15-20 million children under five died every year. In 2023, that number was about 4.9 million. From a much larger total population. Every parent alive today who has never buried a child owes something to the scientists, engineers, and public health workers who made that outcome routine rather than lucky.
Poverty: The Greatest Retreat in History
In 1925, the world had about 2 billion people, and roughly three-quarters of them lived in what economists now call extreme poverty. Subsistence farming, no safety net, no healthcare, constant vulnerability to a bad harvest.
By 2025, with a population of 8 billion (four times as many people), the extreme poverty rate has fallen to under 9%. We went from roughly 1.5 billion people in extreme poverty in 1925 to about 700 million today. With four times the people.
We quadrupled the population and cut the absolute number of people in extreme poverty by more than half. That's not luck. That's what economic freedom and trade and innovation actually do.
The World Bank traces much of this to the post-1990 era, when China's market reforms lifted roughly 800 million people out of poverty. The largest, fastest reduction in human deprivation in recorded history. But the trend predates China. Western Europe, North America, and East Asia all went through their own poverty collapses in the 20th century through industrialization and trade.
Literacy: Reading Is Freedom
In 1925, about 27% of the world's adults could read. Most of humanity, including most women in most of the world, had no access to written knowledge. Books, newspapers, contracts, laws, scientific papers: all closed to them.
Today, 87% of adults worldwide are literate. For young people aged 15-24, it's over 91%. Literacy isn't just an education stat. It's the foundation of economic participation, political voice, and personal freedom. A literate person can read a contract, understand their rights, follow medical instructions, participate in civic life. The spread of literacy is one of the most profound expansions of individual freedom in human history, and nobody talks about it enough.
Child Mortality: The Transformation Nobody Talks About Enough
In 1925, roughly 25 out of every 100 children born died before their fifth birthday. Today, it's 3.7 per 100. The rate dropped by 85%, meaning roughly 10 million additional children survive each year who would have died under 1925 conditions.
The people who made this happen are mostly unknown. The epidemiologists who designed vaccination campaigns. The engineers who built water treatment plants. The agronomists who developed oral rehydration therapy for childhood diarrhea (which alone saves about 1 million lives per year). They didn't get famous. But the lives saved by their work dwarfs every military campaign and political revolution of the 20th century combined.
Democracy: More People Have a Vote
In 1925, there were maybe 20-25 functioning democracies. Mostly Western Europe, North America, Australasia. Most of humanity lived under empires, monarchies, or colonial administrations. No meaningful political representation. And the early totalitarian systems were already gathering steam: Mussolini's Italy, the Soviet Union, fascism spreading across Europe.
Today, roughly 90 countries are classified as democracies or electoral democracies by Freedom House. The number is imperfect and contested. Democracy is a spectrum, not a binary. But more humans in 2025 have a meaningful vote over their government than at any point in history. That trend faces real challenges right now. Over a century, though, the direction is unmistakably positive.
What Actually Drove the Progress
This didn't happen randomly. It followed from a specific set of forces: scientific inquiry, technological innovation, free markets and trade, investment in public health, and the spread of education. None of it was inevitable.
The 20th century also contained two world wars, multiple genocides, a global depression, and decades of nuclear standoff. Progress happened in spite of catastrophic setbacks, not in their absence. That's the important part: the forces of human progress are more powerful than the forces of destruction. A century of data proves it.
What Will 2125 Look Like?
If someone from 1925 could see 2025, they'd think it was science fiction. Diseases that killed millions: gone. Starvation that was routine: rare. Flying across oceans in hours. Carrying the world's knowledge in your pocket. The transformation is that complete.
So here's the question worth sitting with: what will the person in 2125 say when they look back at us?
If the trend holds, they'll probably see a world that's solved or dramatically reduced cancer, Alzheimer's, and major infectious diseases. A world where extreme poverty has been essentially eliminated. Where clean, abundant energy decoupled prosperity from environmental cost. Where the 8 billion people of 2025 contributed something to the compounding wealth of human civilization.
The 20th century's progress was built on the shoulders of the 19th. The 21st century's will be built on the shoulders of the 20th. And on every human alive today who chooses to build, discover, and solve.
You're one of the 8 billion building what comes next.