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Lyman Stone05 September 2024

Why Is Everyone Having Fewer Children? - Lyman Stone - #834

0Frameworks
22Insights

Insights & moments

The myth-busts, hot takes, explainers, and tools worth keeping.

Myth Buster· 4

Myth Buster00:30

Why '6 Kids Per Woman' in 1800 Is a Statistical Illusion

Stone corrects the assumption that historical high birth counts meant huge surviving families. High maternal and child mortality meant the real 'surviving fertility' rate in 1800s America was much closer to modern levels, around 2.7 to 4.

  • US fertility was ~6 births/woman in 1800 (Massachusetts/Connecticut ~4)
  • Many women didn't survive to the end of their reproductive years
  • Many children born didn't survive to adulthood
  • Actual surviving fertility was ~2.7-4, sometimes below 2 in parts of Europe

surviving fertility per woman um in the US was was quite High still um probably you know 2.7 to to 4ish in that range

Lyman Stone · 02:00
#history#demographics#mortality#fertility-rate
Myth Buster16:30

It's Not Poverty — Rising Expectations Are Suppressing Births

Stone argues fertility decline isn't caused by low income. Lottery winners and oil-rich countries have MORE kids when they get richer. The real driver is a rising 'expected standard' of what a child needs, distinct from actual income level.

  • Wealth studies (lottery winners, oil-discovery countries) show richer people have more kids, not fewer
  • Fertility fell in many countries before industrialization; it didn't fall in early-industrializing UK for a long time
  • The real driver is a cultural/expectation shift about what a child 'needs,' not income level itself

if you raise that other one that is your expectations about what you should have or what a child should have have fertility tends to…

Lyman Stone · 17:00
#economics#fertility-rate#myth#cost-of-living
Myth Buster40:00

That '47% Don't Want Kids' Headline Is Misleading

Stone corrects a widely-cited Pew stat implying nearly half of under-50s don't want kids. The actual share of all young people who don't want kids is closer to 20-25%; the 47% figure applied only to the already-childless subgroup citing that specific reason.

  • The Pew '37% to 47%' increase referred to childless people citing 'don't want kids' as their reason, not the whole population
  • Actual population-wide share of young people not wanting kids is roughly 20-25%
  • Desires are polarizing — more clustering at zero and at three-or-four — rather than uniformly declining

the actual prevalence of young people who say they don't want to have kids was 20 something percent

Lyman Stone · 40:00
#surveys#fertility-rate#pew-research#myth
Myth Buster60:30

Falling Sperm Counts Are Mostly Not Real

Stone dismisses popular claims about collapsing sperm counts and testosterone as largely unsupported by scientifically studied cohorts, and says current evidence on microplastics and hormonal contraception shows no long-term fertility damage — just a modestly longer time-to-pregnancy.

  • Sperm counts are not falling in scientifically studied cohorts — described as 'basically fake'
  • Testosterone measurement is unreliable and noisy, undermining 'falling testosterone' claims
  • Hormonal contraception can delay time-to-pregnancy by a few months after stopping, but shows no long-term fundability damage
  • Time-to-pregnancy and miscarriage rates for actively-trying couples haven't changed in decades

sperm counts are not falling in scientifically studied cohorts um this is basically fake

Lyman Stone · 60:30
#fertility-myths#contraception#reproductive-health#science

Hot Take· 1

Hot Take43:30

Stop Talking About a 'Fertility Crisis' — It's Backfiring

Stone argues pronatalists' apocalyptic 'demographic winter' rhetoric is counterproductive, because depression, anxiety, and pessimism about the future are the strongest individual predictors of not wanting kids — doom messaging deepens the very pessimism suppressing births.

  • Best predictor of not wanting kids is depression/anxiety/pessimism about the future, not economics
  • Catastrophizing rhetoric ('demographic winter,' 'going extinct') reinforces the pessimism that drives low fertility
  • His advice: convince people the future isn't awful, rather than push crisis framing

if you actually want people to have kids shut up about a crisis

Lyman Stone · 46:30

the best predictor of people not wanting kids is depression and anxiety

Lyman Stone · 45:30
#mental-health#pronatalism#hot-take#culture

Explainer· 12

Explainer00:00

America's Fertility Rate Has Halved Since 2007

Stone lays out the headline stat: US fertility fell from 2.1 births per woman in 2007 to around 1.6 today. He frames this as roughly half a child missing per woman versus 2007 levels.

  • 2007 US fertility rate: 2.1 births per woman
  • Current rate: ~1.6 births per woman
  • Equivalent to every other woman missing a child versus 2007 rates

in 2007 the average woman had 2.1 kids per woman uh today it's closer to 1.6

Lyman Stone · 00:00
#fertility-rate#demographics#united-states
Explainer03:00

Why Humans Can Interbreed After 10,000 Years Apart

Stone explains a distinctive human trait: extremely low genetic variation in reproductive systems, meaning almost any human can reproduce with any other, unlike some animal species where long-isolated populations lose interfertility entirely.

  • Human populations separated for tens of thousands of years can still produce fertile offspring together
  • Some animal species lose interfertility after long isolation between groups
  • Humans have less body-size variation than most widely distributed animal species
  • A standardized reproductive 'toolkit' helps the species survive shocks

pretty much any human can be fertile with almost any other human

Lyman Stone · 04:00
#biology#genetics#reproduction#evolution
Explainer14:30

The 'Replacement Fertility' Instinct: Why Parents Reused Dead Children's Names

Stone describes 'replacement fertility' — the historical pattern where losing a child raised the odds of having another — evidenced in genealogical records where families reused the same name across multiple children who died in infancy.

  • If a child dies, historical and modern data show the odds of having another child rise
  • Genealogical records show names like 'John' reused through several children who died young, chasing a namesake for the father
  • Modern people, mostly unaware of this instinct, are actually raising more surviving children than past generations, even while bearing fewer

we know in modern and ancient societies if a kid dies the odds of having another kid rise

Lyman Stone · 14:30

the next kid also gets named John when he dies at two the next kid is also named John

Lyman Stone · 15:00
#demographics#history#genealogy#child-mortality
Explainer17:30

The Word 'Parenting' Barely Existed Before 1975

Stone cites a striking linguistic data point: usage of the word 'parenting' was almost nonexistent in English texts before 1975, then exploded across fiction, legal, and general writing in the 80s, 90s, and 2000s — reflecting a new cultural preoccupation with intensive child-rearing.

  • 'Parenting' as a term is rare in text corpora before 1975-1980
  • Frequency explodes across fiction, legal, and general English texts in the 80s-2000s
  • Reflects rising expectations of what parents must actively provide, not just keep children alive

there has never been an era as preoccupied with parenting strategies... as a current one

Lyman Stone · 18:30
#culture#parenting#language#history
Explainer20:00

The Baby Boomer 'Outsourced' Parenting Model

Stone explains that mid-20th-century parenting was minimal and outsourced to schools, TV, and formula, because the main goal — keeping kids alive — was newly assumed achievable, not because parents didn't care.

  • Breastfeeding rates hit rock bottom (~25%) in the 1940s-50s as formula-feeding dominated
  • Parents outsourced education to schools, morality to church, entertainment to TV
  • This hands-off model coincided with the baby boom (fertility roughly 3-4 per woman)

in the middle of the century it was very outsourced right outsource the feeding outsource the education

Lyman Stone · 20:30
#parenting#baby-boomers#history#culture
Explainer23:30

Why a More Diverse Society Made Parenting More Intensive

Stone connects the rise of 'helicopter,' 'gentle,' and 'free-range' parenting labels to growing awareness of social heterogeneity — parents no longer trust that school, TV, or community will replicate their values, so they take on active value-transmission themselves.

  • Widening intergenerational value gaps in the 70s-80s made hands-off parenting look like it had backfired
  • Parents realized they couldn't assume institutions would share their values
  • Branded parenting styles (helicopter, gentle, free-range) emerged as attempts to intentionally replicate personal values
  • This makes parenting feel like a long, costly to-do list

they are looking for parenting strategies that they never learned as a child... to replicate their values in the Next Generation

Lyman Stone · 25:30
#parenting#culture#values#generations
Explainer27:30

The UBI Pilot Study: Where Did the Money Go?

Stone breaks down results from a major cash-transfer/UBI pilot: for every dollar given, earnings fell about 25 cents, spending rose 40-45 cents, and net worth actually declined about 6 cents, with no measurable improvement in health, stress, or housing conditions.

  • Earnings declined ~25 cents per $1 given
  • Spending rose ~40-45 cents, with the biggest increase in gifts, plus food and vacations
  • Net worth declined ~6 cents per $1, leaving a large unexplained residual
  • No significant improvements found in physical health, objective housing conditions, or long-run stress

for every dollar you gave them their earnings declined I think it was like 25 cents

Lyman Stone · 27:30

we found no effect of the transfer across several measures of physical health

Lyman Stone · 31:30
#ubi#economics#policy#research
Explainer37:30

Americans Want 2.3 Kids But Are Having 1.6

Stone lays out three distinct fertility measures — ideal desire (2.3), realistic intention (1.85-2.1), and actual births (1.6) — showing Americans fall well short of both their stated wants and even their own realistic expectations.

  • Ideal/desired family size in US surveys is consistently around 2.3
  • 'Intended' fertility (realistic self-assessment) ranges 1.85 to 2.1
  • Actual fertility is 1.6 — about 0.7 short of desires and 0.2-0.5 short of intentions

people are way short they're about... kits short of what they want

Lyman Stone · 39:00
#fertility-rate#surveys#desires#demographics
Explainer51:00

Childless People Underestimate How Hard Childlessness Gets

Stone discusses Pew survey data comparing young childless people's expectations against older childless people's lived experience — actual challenges like disconnection, loneliness, and lost friendships were consistently worse than young people anticipated.

  • Young people underestimate difficulties of childlessness across categories: disconnection from the next generation, lost friendships, loneliness
  • Not all childless people regret it, but the overall trend is toward underestimating downsides
  • Retirement-age 'free solo' life is less good than younger people expect

young people were... underestimating just how big the difficulties challenges and regrets can be

Lyman Stone · 51:30
#childlessness#surveys#aging#regret
Explainer53:00

It's Not Fewer Kids Per Marriage — It's Fewer Marriages

Stone identifies the primary driver of the fertility decline: married couples' fertility hasn't dropped much, but marriage itself is being delayed or skipped entirely, despite stable desire for both marriage and children.

  • Fertility among married people has barely declined
  • About 90% of people still say they want to marry, typically by their mid-to-late 20s
  • If marriage rates had stayed at 2007 levels, fertility would have declined far less — most of the gap is a 'marriage shortfall'

if everyone got married at the same rates they did in 2007 fertility would not have declined nearly as much

Lyman Stone · 54:00
#marriage#fertility-rate#dating#demographics
Explainer55:00

Young Men's Falling Income Is Shrinking Marriage and Births

Stone ties the marriage decline to a specific economic fact: men in their 20s have gotten poorer in inflation-adjusted terms over the past 20-30 years even as men's incomes overall rose — and men's income at marriage age strongly predicts fertility.

  • On dating apps, women swipe on men's income the way men swipe on physical attractiveness, a pattern Stone says is roughly 600,000 years old
  • Men in their 20s have seen real income declines over 20-30 years, unlike older men
  • Fertility has risen at ages (30s-40s) where men's incomes are rising, but not enough to offset losses from the 20s

men in their 20s are actually getting poorer in inflation adjusted terms

Lyman Stone · 56:00
#economics#marriage#gender#dating
Explainer69:30

Republican Officials Have Nearly Double the Kids of Democrats

Stone cites a striking data point on political polarization and fertility: federal Republican officials average about 2.6 kids versus about 1.4 for Democrats — while cautioning that low heritability of political values means this gap won't reliably shift long-term elections.

  • Republican federal officials average ~2.6 kids vs. ~1.4 for Democrats
  • Democrats are actually closer to the societal fertility average, making Republicans the demographic outliers
  • Social/political values are only 3-40% heritable versus ~80% for height, and conversion plus assimilation offset any fertility-driven ideological shift

the average fertility rate of Republican elected officials at the federal level is something like 2.6 kids and the average fertility rate of democratic ones…

Lyman Stone · 69:30
#politics#fertility-rate#polarization#heritability

Story· 2

Story32:30

Giving Homeless People $1,000/Month Didn't Reduce Homelessness

Stone cites a study that gave homeless individuals $1,000 a month with the explicit goal of getting them housed. After three years of follow-up there was no measurable difference in homelessness rates versus a control group.

  • Three-year follow-up study on homeless cash recipients
  • No measurable difference in homelessness rate between $0 and $1,000/month groups
  • Illustrates that cash alone doesn't fix poverty when other underlying factors are the real barrier

giving homeless people money did absolutely nothing to get them in house

Lyman Stone · 33:00
#ubi#homelessness#policy#research
Story76:00

Why the Amish Will Never Take Over — Even With 6+ Kids Each

Despite very high fertility, Stone's simulation models show the Amish population will never exceed roughly 7% of the US population, because assimilation and conversion out of the group are powerful enough to cap growth even against a large fertility advantage.

  • Simulation using real-world Amish fertility and conversion rates caps their population at a maximum of ~7% of the US
  • They likely won't even reach that ceiling
  • Illustrates that high-fertility subgroups don't automatically inherit the future — cultural conversion often matters more than raw birth rates

the Amish are going to Peak at a maximum of like 7% of American population and they're never actually going to get there

Lyman Stone · 76:30
#amish#demographics#population-modeling#religion

Tool· 1

Tool90:30

Stone's Current Research Focus: Housing as a Pronatalist Lever

Stone shares that his current work leading the pronatalism initiative at the Institute for Family Studies is focused on housing affordability and design, since young people increasingly treat stable housing as a prerequisite milestone before having kids.

  • Young people increasingly live in smaller homes and are less likely to own them
  • Housing is treated as a milestone people feel they need to hit before having kids
  • IFS is researching which housing policies and designs best support the transition to family life, with findings expected in coming months

housing is a major milestone for young people... you shouldn't have kids until your housing situation is kind of sorted out

Lyman Stone · 91:00
#housing#institute-for-family-studies#pronatalism#policy

Takeaway· 2

Takeaway35:30

Conditional Child Allowances Beat UBI for Boosting Births

Stone contrasts unconditional UBI, which doesn't reduce long-term poverty, with conditional cash transfers like child allowances tied to actually raising a child, which reliably increase births and reduce divorce.

  • Child allowances require co-residential custody of a child, unlike a pure UBI
  • Conditional transfers generate slightly more children, less divorce, and more co-residing partners
  • A donor with $20M would get better poverty-reduction results from substance-abuse treatment than from UBI

Ubi where you give people money for nothing not a good policy conditional transfers where you give people money for something can be a decent…

Lyman Stone · 36:30
#policy#child-allowance#ubi#fertility-rate
Takeaway84:00

Fertility Will Bottom Out Between 0.4 and 1.3

Stone gives his forecast for Western fertility: continued decline, likely bottoming somewhere between 0.4 and 1.3 depending on whether the underlying cause is structural (young men's wages) or cultural (parenting norms, which could reverse faster).

  • If driven by intensive parenting norms, those norms could weed out within a few generations, allowing partial recovery
  • If driven by structural economics (young men's wages under skills-biased technical change), the floor may be more durable but not zero
  • Overall estimate: fertility bottoms out between 0.4 and 1.3, with disappointment and 'cope' as the dominant social experience along the way

I think we'll bottom out somewhere between 0.4 and 1.3

Lyman Stone · 84:30

it's going to be a lot of disappointment and a whole lot of cope

Lyman Stone · 87:00
#forecast#fertility-rate#demographics#future