What caused the Baby Boom? To fix today's low birth rates, it helps to know how falling fertility was turned around once before.
Economic growth helped. But it turns out there a cultural closeness between men and women unlike anything before or since! A🧵, please share, follow!
A widely read article explained how new appliances, medical progress and more housing all supported family formation.
But this can't be the whole story, because usually as people are better off, fertility goes down.
There was something special in the air at the time. (2/9)
World War II saw young men involved in the war effort at incredibly high rates. In the US, 25% of men and close to 50% of men ages 18-30 served in the military and a further 25% were employed in war work. Other countries had similar or higher rates of deployment. (3/9)
Young men were seen by young women in a glowing light, both during the war and after returning home. Young men also matured quickly. What followed was an era of warm feelings between men and women across society, that infected a generation. (4/9)
In those days, love meant marriage. And so people married more often and earlier than ever before. In the US, women married at a median age ~20 and 94% of men and women married by age 40!
It turns out that lots of marriages at early ages are the key to high fertility. (5/9)
Economic tailwinds helped. But it takes culture to truly explain how births soared in so many different countries around the same time. (Chart from @WorksInProgMag.) (6/9)
If more and younger marriages gave us the Baby Boom, are they an answer for today? Yes, and here is important thread on that! (7/9)
You can get a sense of the very positive atmosphere that existed then between men and women by watching clips of couples from that era.
Here is a couple who married in 1941 and served in the war, talking about love after their 77th anniversary. (8/9)
If you enjoyed or learned something from this thread on the causes of the Baby Boom, and lessons for today, please repost. Also follow and spread the word about this account, which is dedicated to solutions to our fertility crisis. (9/9)
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A just-published paper introduces a new metric: the ratio of births observed (Bo) to births needed (Bn) to make up for deaths.
When Bo/Bn is below 1, a population faces natural decline.
With this lens, the dire situation of Europe and East Asia is thrown into stark relief. 🧵.
Most often we rely on TFR, births per woman of childbearing age. But that ignores the age structure of a population.
Japan is an old country with few women of childbearing age, and deaths far outnumber births.
India is a young country, and births still greatly exceed deaths. 2/
East Asia has less than half of the births needed to make up for deaths each year, indicating rapid demographic collapse. Conditions have gotten much worse since 2000, as these countries went from young to old.
Southern and Eastern Europe aren't much better in this regard. 3/6
Turkey's astonishing fertility collapse
Turkey's president Erdoğan made it his mission to revive birthrates. Instead, Turkish fertility has fallen faster than almost anywhere on Earth to just 1.42 in 2025 (just 1.2 outside of Kurdistan).
What happened, and what can we learn? 🧵.
By every measure, Recep Tayyip Erdoğan has been a failure in the thing that mattered most to him, getting Turks to have more children.
Why? It doesn't help that Erdoğan is deeply unpopular with young people. 2/8
(Chart by @JesusFerna7026)
As demographer @lymanstoneky explains in a wonderful new article, the biggest direct cause of falling fertility is falling marriage.
When marriage falls, fertility plummets in a traditional country like Turkey where almost all childbearing is within wedlock. 3/8
India's new birth report just revealed a TFR of 1.88, a little below replacement.
But unlike most countries, 🇮🇳 does not have a crisis of low births. With its young population, India had 23 million births, 3x more than any other country.
In Europe, Finland, Sweden, the Netherlands, Germany, Switzerland, Spain, Portugal and Greece are all showing an absolute increase in births in 2026.
That is impressive considering that the average age in the EU is 45 and there are fewer women of childbearing age every year. 2/4
In East Asia on the other hand, the ongoing fertility collapse is accelerating.
Births are down 18% in Taiwan and 21% in Hong Kong, with massive drops in Thailand and Macao as well. This bodes poorly for China, which will likely have a fertility well below 1.0 this year. 3/4