All key figures
164 cited figures from across the nine factors, in one table. Figures that are model-based, debated, or correlational are labeled as such.
| Factor | Measure | Value | Source |
|---|---|---|---|
| Biological | Deaths from noncommunicable diseases, 2021 | At least 43 million, 75% of non-pandemic deaths | WHO fact sheet on noncommunicable diseases |
| Biological | Noncommunicable disease deaths before age 70 | 18 million, 82% of them in low- and middle-income countries | WHO fact sheet on noncommunicable diseases |
| Biological | People living with obesity, 2022 | 1 in 8 worldwide, including 890 million adults | WHO obesity and overweight fact sheet |
| Biological | Adults who were overweight, 2022 | 2.5 billion (43%) | WHO obesity and overweight fact sheet |
| Biological | Growth in obesity since 1990 | Adult obesity more than doubled, adolescent obesity quadrupled | WHO obesity and overweight fact sheet |
| Biological | Adults not meeting recommended activity levels, 2022 | 31%, about 1.8 billion people, up about 5 percentage points since 2010 | WHO (2024) |
| Biological | Physical inactivity by sex, 2022 | 34% of women, 29% of men | WHO (2024) |
| Biological | Original ACE study | 9,508 adults, more than half reported at least one adverse childhood experience. Four or more categories carried 4 to 12 times the risk of alcoholism, drug abuse, depression, and suicide attempt | Felitti et al. (1998) |
| Biological | ACE meta-analysis | 37 studies, 253,719 participants. Four or more ACEs raised risk for all 23 outcomes. Odds ratios were under 2 for inactivity, obesity, and diabetes and over 7 for problematic drug use and violence | Hughes et al. (2017) |
| Biological | Children under 5 stunted, 2024 | 150.2 million (23.2%), down from 40% in 1990 | WHO, UNICEF, and World Bank Joint Child Malnutrition Estimates, 2025 edition |
| Biological | Progress toward the 2030 stunting target | At current progress the target will be missed by 46 million children | WHO, UNICEF, and World Bank Joint Child Malnutrition Estimates, 2025 edition |
| Biological | Children under 5 wasted, 2024 | 42.8 million | WHO, UNICEF, and World Bank Joint Child Malnutrition Estimates, 2025 edition |
| Biological | Long-term effects of childhood undernutrition | Shorter adult height, less schooling, and reduced economic productivity. Height-for-age at 2 years was the best predictor of human capital | Victora et al. (2008), cohorts from five countries |
| Biological | Child deaths linked to undernutrition | Around 45% of deaths among children under 5, and wasted children face a higher risk of death if not treated. The estimate comes from a 2013 Lancet analysis (Black et al., 2013) and is still cited by WHO. These deaths remove potential future contributors, including possible pioneers, before any ability can develop | WHO malnutrition page |
| Biological | Low birth weight, 2020 | 19.8 million newborns, 14.7% of all live births (under 2,500 grams), down from 16.6% in 2000. South Asia accounted for 44%. Birth weight data were unavailable for 28.7% of newborns, so the global figure is partly modeled | UNICEF and WHO (Okwaraji et al., 2024) |
| Biological | Norwegian twin study of birth weight | The effects of birth weight on long-run outcomes such as height, IQ, earnings, and education were significant and similar in size to simple comparisons across all children, even though short-run effects within twin pairs were much smaller | Black, Devereux, and Salvanes (2007) |
| Biological | Newborn deaths from preterm or small-for-gestational-age births, 2020 | 55.3% of 2.4 million newborn deaths worldwide. About three quarters of these were preterm. The estimate covers these two groups, which overlap heavily with low birth weight but are not identical to it | Lawn et al. (2023) |
| Biological | First-year mortality in Danish children born 1981 to 1995 | 0.6% overall and 6.6% among babies under 2,500 grams | Maruyama and Heinesen (2020) |
| Biological | Twin studies of birth weight, United States and Sweden | Found similar effects on education and income, though the U.S. effects were generally small. The Swedish study also linked lower birth weight to higher adult mortality | Royer (2009), Bharadwaj et al. (2018) |
| Biological | Danish study of birth weight | About two million births from 1981 to 2013, using a pregnancy complication that causes early birth, confirmed causal effects on infant death, health, and disability but found no strong evidence for effects on test scores, income, or IQ. The effect on infant deaths has weakened as newborn care has improved | Maruyama and Heinesen (2020) |
| Biological | Sickle cell disease worldwide, 2021 | An estimated 7.74 million people were living with it and 515,000 babies were born with it, mostly in the Caribbean and western and central sub-Saharan Africa. Deaths recorded as caused by it numbered 34,400, but deaths it contributed to totaled about 376,000, including 81,100 children under 5 | GBD 2021 Sickle Cell Disease Collaborators (2023) |
| Biological | Sickle cell disease and child mortality in Africa | Available data are consistent with 50% to 90% of children with the most common form dying in early childhood. The reviewers state that the data are inadequate for definitive statements | Grosse et al. (2011) |
| Biological | School performance with sickle cell disease, United States | Students scored 0.70, 0.87, and 0.80 standard deviations below norms in reading, math, and spelling, and repeated a grade about 10 times as often as Black students nationally. Students who had a stroke or silent stroke scored lower. Environmental factors such as socioeconomic status are also associated with cognitive outcomes in this group | Heitzer et al. (2021), Prussien et al. (2020) |
| Biological | Newborn deaths and child deaths from congenital disorders | An estimated 240,000 newborns in their first 28 days each year and 170,000 more children aged 1 month to 5 years. Nine of ten children born with a serious congenital disorder live in low- and middle-income countries. Congenital disorders have genetic and non-genetic causes | WHO (2023) |
| Biological | Phenylketonuria screening and treatment | Newborn screening and early dietary treatment substantially improve brain development and prevent the severe intellectual disability the disorder otherwise causes. Even with early treatment, children often score below the IQ predicted from their parents and siblings | U.S. Preventive Services Task Force (2008), NICHD |
| Biological | Origin of the sickle cell gene in tropical regions | The gene became common because carriers, who have one copy, are more likely to survive malaria. This links the barrier to the malaria barrier | Uyoga et al. (2019) |
| Biological | Sleep restriction experiment | 48 adults randomized to 4, 6, or 8 hours in bed for 14 days. 6 hours or less produced cognitive deficits equal to up to 2 nights of total sleep deprivation, and participants were largely unaware of their decline | Van Dongen et al. (2003) |
| Biological | Deaths caused by alcohol and psychoactive drugs, 2019 | 2.6 million from alcohol (4.7% of all deaths) and 0.6 million from drugs. Men accounted for 2 million alcohol deaths and 0.4 million drug deaths | WHO (2024) |
| Biological | People with alcohol use disorders, 2019 | An estimated 400 million, including 209 million with alcohol dependence | WHO (2024) |
| Biological | Adolescent cannabis use and schooling | Combining three Australian and New Zealand cohorts (3,765 people), those who used cannabis daily before age 17 had about 63% lower odds of finishing high school and 62% lower odds of earning a degree than those who never used it, after adjusting for many background factors. Whether cannabis causes this or marks earlier disadvantage is debated, and a published letter noted daily users did no worse than weekly users on schooling | Silins et al. (2014) |
| Psychological | People living with a mental health condition | More than 1 billion, roughly 1 in 8. Anxiety and depressive disorders are the most common | WHO (2025) |
| Psychological | Working days lost to depression and anxiety each year | An estimated 12 billion, costing about US$1 trillion in lost productivity | WHO fact sheet on mental health at work |
| Psychological | Size of loss aversion | The often-quoted figure that losses weigh 2.25 times as much as gains comes from Tversky and Kahneman (1992), a study of 25 graduate students, not from the 1979 prospect theory paper. A 2024 meta-analysis of 607 estimates from 150 articles found an average of 1.96. A separate meta-analysis of risky choices found a smaller average of 1.31, so the size of loss aversion depends on the setting | Brown et al. (2024), Walasek et al. (2024) |
| Psychological | Learned helplessness, revised view | Passivity is the default, control must be learned | Maier and Seligman (2016) |
| Psychological | Replication of 100 published psychology studies | 97% of the originals had significant results, but only 36% of the replications did. Replication effects averaged half the size of the originals | Open Science Collaboration (2015) |
| Psychological | Mindset and achievement, two meta-analyses | 273 studies (365,915 people) on mindset and achievement and 43 studies (57,155 people) on mindset interventions. Overall effects were weak in both, though students with low socioeconomic status or at academic risk may benefit | Sisk et al. (2018) |
| Psychological | Online mindset intervention of under one hour | Improved grades among lower-achieving students and increased enrollment in advanced math, mainly in schools where peer norms supported the message | Yeager et al. (2019), nationally representative U.S. sample |
| Psychological | Dark Triad traits and work behavior | A meta-analysis of 245 samples (43,907 people) found that narcissism, Machiavellianism, and psychopathy were all associated with counterproductive work behavior, and Machiavellianism and psychopathy with lower job performance. The effects depended on context, including authority and culture | O'Boyle et al. (2012) |
| Psychological | Narcissism and leadership | Narcissism predicts who emerges as a leader, largely through extraversion, but not how effective leaders are. Narcissistic leaders rate themselves as more effective, while supervisors, subordinates, and peers do not. Moderate narcissism appeared best | Grijalva et al. (2015) |
| Psychological | Narcissistic CEOs | Among 111 computer-industry CEOs, narcissism was linked to bold strategies, more and larger acquisitions, and extreme, fluctuating results, but not to better or worse performance overall | Chatterjee and Hambrick (2007) |
| Psychological | Dispositional greed | People higher in dispositional greed kept more money for themselves in economic games, judged transgressions more acceptable, and were more likely to accept a bribe in a laboratory study. Greed was linked to lower self-control and life satisfaction | Seuntjens et al. (2015, 2019) |
| Psychological | Social class and unethical behavior | A widely cited claim that higher social class causes unethical behavior (Piff et al., 2012) failed two well-powered, preregistered replications of its field studies. Greed as a trait and wealth are different things | Jung et al. (2023) |
| Psychological | Childhood conduct problems and later costs, Dunedin cohort | The 9% whose childhood conduct problems persisted into adulthood accounted for 53% of all criminal convictions and 25% of welfare benefit months | Rivenbark et al. (2018) |
| Psychological | Concentration of costs, Dunedin cohort | One-fifth of members accounted for 81% of criminal convictions, 66% of welfare benefits, and 57% of hospital nights. Poor brain health at age 3 predicted this group | Caspi et al. (2016) |
| Psychological | Concentration of costs in 4 million people | The same concentration of costs in a small population segment appeared in records of 1.7 million New Zealanders and 2.3 million Danes. That segment had early-life disadvantages, including low education and poor mental health | Richmond-Rakerd et al. (2020) |
| Psychological | Economic impact of violence, 2025 | $21.8 trillion, or 10.5% of global GDP. Most of this is military and internal security spending, not individual behavior. Homicide was about 6% of the total in the previous year's estimate | Institute for Economics and Peace (ThisDay, 2026, and Vision of Humanity) |
| Psychological | Selective exposure to information | A meta-analysis of 91 studies with nearly 8,000 participants found a moderate preference for information that supports existing views over information that challenges them (d = 0.36). The bias was stronger in more closed-minded people and when beliefs were tied to values, and it reversed when challenging information was useful for a current goal | Hart et al. (2009) |
| Psychological | Gym memberships and present bias | Among 7,752 members of three U.S. health clubs, those who chose a flat monthly fee of over $70 attended on average 4.3 times a month, paying more than $17 per visit when a 10-visit pass cost $10 per visit. On average they gave up about $600 over their membership. The authors attribute this to overconfidence about future self-control. Later research debates the explanation: a membership may serve as a commitment device, people may simply overpredict how often they will go (one experiment found predictions about three times actual attendance), or they may prefer a single payment | DellaVigna and Malmendier (2006), Acland and Levy |
| Psychological | How common learned helplessness is | No large study of how common learned helplessness is in people was found. Maier and Seligman (2016) revised the original theory using animal neuroscience, concluding that passivity is the default response to prolonged adversity and that a sense of control must be learned. The Ethiopian aspirations trial under cultural factors is the closest human evidence that expectations of what is possible can be changed. Laboratory studies in people show a pattern consistent with the theory: in one, a single failure improved later performance while four failures worsened it (Mikulincer, Kedem, and Zilkha-Segal, 1989). Critics argue such deficits can arise from causes other than expecting future lack of control, and that artificial lab tasks may not generalize (Silver, Wortman, and Klos, 1982). No study linking learned helplessness to real-world achievement was found, so this barrier is rated C | Maier and Seligman (2016), Mikulincer et al. (1989) |
| Psychological | Cognitive dissonance replication | A preregistered replication in 39 labs with nearly 4,900 people found that writing an essay against one's own view shifted attitudes, but having a choice about writing it made no difference, contradicting the classic prediction. The selective exposure meta-analysis above supports the related prediction that people avoid information that conflicts with their beliefs | Vaidis et al. (2024), Hart et al. (2009) |
| Economic | People in extreme poverty (below US$3.00 a day) | About 831 million in 2025, roughly 1 in 10, down from about 2.3 billion in 1990. A March 2026 update revised the 2024 count to 847 million and projected the rate to fall from 10.4% in 2024 to 10.0% in 2026 | World Bank (Fall 2025, March 2026) |
| Economic | People in poverty at the US$8.30 a day line, 2025 | An estimated 3.7 billion | World Bank (Fall 2025) |
| Economic | Children in households below US$3.00 a day, 2024 | An estimated 412 million | World Bank (Fall 2025) |
| Economic | Change to the extreme poverty line, June 2025 | Raised from US$2.15 to US$3.00 a day, adding about 125 million people. Older figures near 700 million used the previous line | World Bank (June 2025) |
| Economic | Share of global wealth | Top 10% own about 75%, bottom 50% hold about 2%, top 1% hold 37% | World Inequality Report 2026 |
| Economic | Share of global income | Top 10% receive 53%, bottom 50% receive 8% | World Inequality Report 2026 |
| Economic | Upward mobility, bottom to top income fifth (U.S. cities) | 4.4% (Charlotte) to 12.9% (San Jose) | Chetty et al. (2014) |
| Economic | Inventor rates by parents' income | Children whose parents are in the top 1% of income become inventors at a rate of 8.3 per 1,000, compared with 0.85 per 1,000 for children of below-median-income parents. Early ability explains little of this gap: top-scoring third graders are much more likely to become inventors only if their families have high incomes. By 8th grade, test scores explain half the gap, because low-income children steadily fall behind | Bell et al. (2019), authors' summary |
| Economic | Third-grade math scores and the innovation gap | In the conference version of the study, third-grade math scores account for less than one-third of the income gap in innovation | Bell et al. (2018), conference version |
| Economic | Patenting at the most innovative colleges | At colleges such as MIT, students from low- and high-income families patent at similar rates. The authors conclude that childhood environment and exposure drive most of the gap, rather than lack of funding or aversion to risk | Bell et al. (2019) |
| Economic | Great Gatsby Curve | Across rich countries, higher income inequality goes with lower mobility between generations (Corak, 2013). Corak has said it is not a causal relationship, while also arguing that dismissing it as mere correlation is too glib. Critics argue that with a different mobility measure, the United States has upward mobility similar to Canada and Sweden despite very different inequality (Winship, 2015). Durlauf and Seshadri (2018) propose that inequality reduces mobility by increasing residential segregation, a model-based argument. Within the United States, Chetty et al. (2014) found lower mobility in areas with greater inequality, also a correlation | Corak (2013), Winship (2015), Durlauf and Seshadri (2018), Chetty et al. (2014) |
| Economic | Income versus wealth in the mobility and inventor studies | These studies measure parents' income, not wealth. The global wealth figures above are rated C because many countries' wealth shares are estimated rather than measured | Strength ratings |
| Economic | Perry Preschool Program, annual social rate of return | About 7% to 10%, lower than earlier claims but above the historical return on U.S. stocks. The program was small (58 treated children), so generalizing its results requires caution | Heckman et al. (2010) |
| Economic | Researchers needed to double computer chip density vs. early 1970s | More than 18 times | Bloom et al. (2020) |
| Economic | Long working hours | In 2016, an estimated 488 million people (8.9% of the world's population) worked 55 or more hours a week. WHO and ILO attributed 745,000 deaths from stroke and heart disease that year to these long hours, a 29% increase since 2000. Working 55 or more hours was associated with a 35% higher risk of stroke and a 17% higher risk of dying from heart disease than working 35 to 40 hours. Independent epidemiologists argued the heart disease conclusion does not meet the reviewers' own evidence standards, because the link was weaker and not statistically significant in the higher-quality studies. The review authors replied that their conclusion stands, so the death estimates are contested | Pega et al. (2021), Kivimäki et al. (2020) |
| Economic | Short-termism, survey of executives | In a survey of 401 financial executives plus 20 interviews, 78% said they would give up economic value to smooth reported earnings, and many said they would delay valuable projects to meet short-term earnings targets. This measures stated willingness, not observed decisions | Graham, Harvey, and Rajgopal (2005) |
| Economic | Short-termism, public versus private firms | Comparing matched U.S. firms, private firms invested nearly 10% of assets a year against about 4% for public firms, and were about four times more responsive to new investment opportunities. Firms invested more in the five years before going public than after, and the gap was largest where stock prices react most to earnings news. The study assumes private firms face less short-term pressure, and later studies using other data found public firms invest as much or more (Gilje and Taillard, 2016, Feldman et al., 2021), so the finding is debated | Asker, Farre-Mensa, and Ljungqvist (2015) |
| Economic | Adult learning barriers | In the 2023 Survey of Adult Skills, about one in four adults across OECD countries reported a barrier to participating in adult learning. Among them, lack of time due to work or family was the most common reason (48%), ahead of a lack of suitable training (14%) and cost (13%). These are self-reported reasons | OECD, Trends in Adult Learning (2025) |
| Societal | People forcibly displaced, end of 2024 | 123.2 million, nearly double the figure a decade earlier | UNHCR Global Trends 2024 |
| Societal | People forcibly displaced, end of 2025 | 117.8 million, 5.4 million fewer than a year earlier and the first decrease in a decade, but still about 1 in 70 people worldwide | UNHCR Global Trends 2025 |
| Societal | Corruption Perceptions Index, 2025 | Global average dropped for the first time in more than a decade, to 42 out of 100. 122 of 182 countries (67%) scored below 50. Only 31 countries have improved their scores since 2012 | Transparency International |
| Societal | Rule of Law Index, 2025 (143 countries, 95% of the world's population) | Rule of law declined in 68% of countries, up from 57% the previous year, the eighth straight year in which more countries declined than improved | World Justice Project |
| Societal | Rule of Law Index, specific measures, 2025 | Freedom of opinion and expression fell in 73% of countries, and judicial limits on government power declined in 61% | World Justice Project |
| Societal | Premature chronic disease deaths in low- and middle-income countries, 2021 | 82% | WHO (see the biological factor) |
| Societal | Health gradient by social position | Declines step by step at each lower level | Marmot (2004) |
| Societal | U.S. hiring field experiments | A meta-analysis of every available U.S. hiring field experiment (28 studies, 55,842 applications for 26,326 positions) found that since 1989, white applicants received on average 36% more callbacks than African Americans and 24% more than Latinos. There was no change in discrimination against African Americans over 25 years and modest evidence of a decline for Latinos, which the authors treat cautiously because few studies included Latino applicants | Quillian et al. (2017) |
| Societal | Hiring discrimination in nine countries | Across 97 field experiments with more than 200,000 applications in nine countries in Europe and North America, discrimination against nonwhite natives appeared in every country. In the highest-discrimination countries, white natives received nearly twice the callbacks of nonwhites, and in the lowest, about 25% more. France had the highest rates, followed by Sweden | Quillian et al. (2019) |
| Societal | Discrimination at large U.S. employers | A field experiment sending more than 83,000 fictitious applications to 108 of the largest U.S. employers found distinctively Black names reduced the chance of employer contact by 2.1 percentage points. Discrimination was concentrated: the fifth of firms that discriminated most accounted for nearly half of lost contacts to Black applicants. There was no average gender gap, but some firms favored men and others favored women | Kline, Rose, and Walters (2022) |
| Societal | Allocation of talent, 1960 to 2010 | In 1960, 94% of U.S. doctors and lawyers were white men. By 2010 the share was 62%. A model-based study estimated that improved allocation of talent, as women and Black men entered occupations previously closed to them, explains 20% to 40% of U.S. growth in output per person from 1960 to 2010 | Hsieh, Hurst, Jones, and Klenow (2019) |
| Societal | Women's legal rights worldwide | Women have about two-thirds (67%) of the legal rights of men worldwide. Only 4% of women live in economies close to full legal equality, and no economy grants women equal economic opportunities. Fewer than half (47%) of the policies and institutions needed to make these laws effective are in place. Between 2023 and 2025, 68 economies enacted 113 reforms | World Bank, Women, Business and the Law 2026 |
| Societal | Discrimination in science funding | Black applicants' chance of winning a major NIH research grant was about 10 percentage points lower than white applicants' (Ginther et al., 2011). A 2019 NIH analysis of 2011 to 2015 applications found award rates of 10.7% for African American or Black applicants and 17.7% for white applicants. Topic choice explained over 20% of the gap after controlling for prior achievements, leaving most of it unexplained. An unexplained gap is not by itself proof of reviewer bias | Ginther et al. (2011), Hoppe et al. (2019), Taffe and Gilpin (2021) |
| Societal | Gender bias in academic hiring, a contested finding | Moss-Racusin et al. (2012) found 127 science faculty rated an identical lab-manager application as more competent and hireable when it carried a male name. Williams and Ceci (2015) found 873 faculty preferred equally qualified women about 2:1 for hypothetical tenure-track positions, though critics argue their design did not reflect real hiring. A larger replication of Moss-Racusin et al. reported by Jussim and colleagues found the reverse, which the authors list as accepted by Meta-Psychology, but it had not appeared there as of October 7, 2026. The direction of gender bias in academic hiring therefore depends on the career stage and study design | Moss-Racusin et al. (2012), Williams and Ceci (2015) |
| Societal | Limits of field experiments | Field experiments measure discrimination only at the first step, the callback, so they do not capture what happens in interviews, pay, or promotion. They also face a methodological critique (Heckman and Siegelman, 1993): if employers perceive more variation in unobserved qualities for one group, callback gaps can misstate discrimination in either direction. Reanalyses using a correction method developed by Neumark (2012) found most estimates robust, though a Swedish reanalysis found the critique mattered for some studies | Neumark (2012), Neumark and Rich (2016) |
| Societal | Racial gaps in mobility across generations | In U.S. tax and census records covering nearly the whole population, Black and American Indian children have much lower rates of upward mobility and higher rates of downward mobility than white children. Comparing children from families with the same income, the Black-white gap is driven by lower wages and employment among Black men, with no such gap between Black and white women. Parental marital status, education, and wealth explain little of it, and Black boys have lower adult incomes than white boys from comparable-income families in 99% of Census tracts | Chetty, Hendren, Jones, and Porter (2020) |
| Societal | 1930s redlining maps | A federal agency graded neighborhoods for lending risk, and the lowest-graded areas often had mostly African American residents. Comparing areas on either side of the map boundaries in 149 cities, the maps led to lower homeownership, house values, and rents and to more racial segregation in later decades. Later research disputes the mechanism: the agency that drew the maps lent widely in low-graded neighborhoods and drew them after most of its lending was done, while the Federal Housing Administration had already been excluding these neighborhoods by its own methods. The long-run gaps are well documented, but whether the maps themselves caused them is contested | Fishback, Rose, Snowden, and Storrs (2021), Aaronson, Hartley, and Mazumder (2021) |
| Societal | Racial gaps in mortgage lending | Latinx and Black borrowers with the same credit risk paid significantly higher interest rates on government-backed mortgages, costing them over $450 million a year. Algorithmic lenders showed similar gaps for some loans and smaller gaps for others. The widely quoted figures of 7.9 basis points and $765 million come from the 2019 working paper, not the published version | Bartlett, Morse, Stanton, and Wallace (2022) |
| Societal | Racism and health | A meta-analysis of 293 studies, mostly from the United States, found that reported racism was associated with poorer mental health (r = -0.23), including depression and anxiety. Associations were stronger in cross-sectional and non-representative studies, so how much is causal is uncertain | Paradies et al. (2015) |
| Societal | Same-race teachers, what helps | In the Tennessee STAR experiment, Black students randomly assigned at least one Black teacher in kindergarten through third grade were 9 percentage points (13%) more likely to graduate from high school and 6 percentage points (19%) more likely to enroll in college. There was no effect on white students, and North Carolina data gave similar results. The authors suggest role-model effects as one possible channel. A review of 37 studies found benefits of student-teacher racial matching, especially for Black and Latino students | Gershenson et al. (2022), Redding (2019) |
| Societal | Racial discrimination in the European Union | A survey of 6,752 people of African descent in 13 EU countries found 45% experienced racial discrimination in the previous five years, up from 39% in 2016, and 34% when looking for work. Only 9% reported it. Germany had the highest rate | EU Agency for Fundamental Rights (2023) |
| Societal | A caution on implicit bias | Measured discrimination, as in the field experiments above, is stronger evidence than scores on implicit bias tests. A meta-analysis of 492 studies (87,418 participants) found that procedures can change implicit bias scores, but those changes produced trivial changes in behavior and did not explain behavior change. An earlier meta-analysis described the Implicit Association Test as a poor predictor of discriminatory behavior. The test's developers replied that small effects can still matter across large populations, but acknowledged the test is problematic for identifying which individuals will discriminate | Forscher et al. (2019), Oswald et al. (2013), Greenwald, Banaji, and Nosek (2015) |
| Societal | Scope of the mobility, redlining, and lending studies | The mobility, redlining, and lending studies show large, persistent racial gaps. For redlining, whether the maps themselves caused these gaps is contested. They do not each identify present-day discrimination as the sole cause of the gaps they measure | Strength ratings |
| Societal | Public goods experiments | Contributions fell to very low levels when free riders could not be punished, with 53% to 75% of participants contributing nothing by the final round. When participants could punish free riders, contributions rose toward full cooperation | Fehr and Gächter (2000) |
| Societal | Managing shared resources | A review of 91 studies of real communities managing shared resources supported most of Ostrom's design principles for successful local governance | Cox et al. (2010) |
| Societal | COVID-19 excess deaths, 2020 and 2021 | WHO estimated 14.83 million excess deaths worldwide, 2.74 times the 5.42 million deaths reported as caused by COVID-19. Only about half of countries had complete death data, so many estimates are modeled | Msemburi et al. (2023) |
| Societal | Existential risk estimates | Ord's probability estimates for existential catastrophe are his own judgments, not measurements, so they are not given here as figures | Ord (2020) |
| Societal | Peru's colonial mining mita | In Peru, districts just inside the boundary of the mita, a colonial forced mining labor system in force from 1573 to 1812, have about 25% lower household consumption today and about 6 percentage points more child stunting than districts just outside it. The effect persisted through land tenure and public goods such as roads. Because the boundary was drawn centuries ago, this comparison isolates the effect of an extractive institution better than cross-country studies can | Dell (2010) |
| Societal | Underinvestment in pandemic preparedness | A model combining the frequency and severity of pandemics estimated expected global losses from future pandemics at over $700 billion a year. It found that spending $60 billion up front and $5 billion a year to expand vaccine production capacity would yield an expected net gain of more than $500 billion. A University of Leeds policy brief argues that preparedness return-on-investment claims rest on unreliable assumptions, so the size of the underinvestment is uncertain | Glennerster, Snyder, and Tan (2022), University of Leeds |
| Cultural | Gender Social Norms Index, 2023 (80 countries, 85% of the world's population) | Nearly 9 in 10 men and women hold at least one fundamental bias against women | UNDP |
| Cultural | Beliefs about political and business leadership | About half of people believe men make better political leaders, and more than 40% believe men make better business executives, with no improvement over the previous decade | UNDP |
| Cultural | Child marriage | An estimated 640 million girls and women alive today were married in childhood. About 1 in 5 young women aged 20 to 24 were married as children, down from nearly 1 in 4 a decade earlier. At the current rate, ending the practice would take about 300 years | UNICEF (2023) |
| Cultural | Trust in scientists across 68 countries | 71,922 people surveyed. In most countries, most people trust scientists and want them to engage more in society and policymaking. Trust varied within and between countries, partly by political orientation | Cologna et al. (2025) |
| Cultural | Science literacy and climate polarization | Highest science literacy and numeracy were the most culturally polarized on climate risk, not the least | Kahan et al. (2012) |
| Cultural | Aspirations trial in rural Ethiopia | Households randomly shown a one-hour documentary about people from similar communities who escaped poverty had higher aspirations six months later, along with more saving, borrowing, and spending on children's schooling. Five years later, they had invested more in farming, children's education, and assets | Bernard et al. (2026) |
| Cultural | Materialism and wellbeing | A meta-analysis of 259 samples found materialist values were associated with lower wellbeing (r = -0.19 for the most widely used measures). The link was strongest for risky health and spending behaviors and negative self-views, and weakest for life satisfaction. The studies are correlational. Three longitudinal studies and a small intervention trial found wellbeing improved as people became less materialistic (Kasser et al., 2014), but a three-year study of 6,551 people using a stricter method found no within-person link between changes in materialism and changes in life satisfaction (reported by PsyPost, 2023) | Dittmar et al. (2014) |
| Cultural | Tight and loose cultures | A 33-nation study measured cultural "tightness," meaning strong norms and low tolerance of deviant behavior. Tighter nations (such as Pakistan, Singapore, and Japan) tended to have histories of threats such as dense populations, resource scarcity, conflict, and disease. Looser nations included New Zealand, the Netherlands, and the United States. Tightness can support coordination but leaves less room for nonconformity. The measure is disputed: a six-country replication found different country rankings and did not support averaging individual answers into country scores (Treviño et al., 2021), and another study argued the scoring method can distort results (Venaik et al., 2021). The country examples should be treated as uncertain | Gelfand et al. (2011) |
| Cultural | Trust in scientists in 12 countries, 2020 | In panel surveys in 12 countries from March to December 2020, trust in scientists was the key driver of support for and compliance with non-drug public health measures and of favorable attitudes toward vaccination | Algan et al. (2021) |
| Cultural | Trust in experts and vaccination intentions | In 25 national samples across 12 countries (25,334 people), trust in medical and scientific experts was among the strongest and most consistent correlates of willingness to be vaccinated against COVID-19 (odds ratio 1.28). These are surveys of stated intentions | Kerr et al. (2021) |
| Cultural | Materialism and children's learning | In 9- to 11-year-olds in Britain and Hong Kong, materialism was linked to lower exam performance through weaker interest in mastering material. In Hong Kong it predicted worse grades a year later, and in an experiment British children shown a materialism prime chose easier performance-oriented tasks and gave up on a learning task sooner. Samples were modest. An independent longitudinal study of 404 Hong Kong secondary students found that earlier materialism predicted lower engagement and lower later achievement, partly through reduced motivation (King and Datu, 2017) | Ku, Dittmar, and Banerjee (2014) |
| Cultural | Individualism and innovation | Using the frequency of certain genes and historic disease prevalence as instruments for culture, a cross-country study found that individualism raised innovation, productivity, and income per worker, and the link held after controlling for institutions. The instruments rest on strong assumptions that they affect growth only through culture, so this is rated C | Gorodnichenko and Roland (2017) |
| Social | People who report feeling lonely | About 1 in 6 worldwide (15.8%) | WHO Commission on Social Connection (2025) |
| Social | Deaths linked to loneliness | An estimated 871,000 per year, about 100 every hour | WHO Commission on Social Connection (2025) |
| Social | Loneliness by group | 21% among adolescents, 24.3% in low-income countries, and 11% in high-income countries | WHO Commission on Social Connection (2025) |
| Social | Survival advantage of strong social relationships | About 50% higher likelihood | Holt-Lunstad et al. (2010) |
| Social | Asch conformity experiments | Judging line lengths alone, people erred under 1% of the time (0.7%). With a unanimous group giving wrong answers, 36.8% of responses conformed, 94 of 123 participants (about 76%) conformed at least once, and 29 of 123 (about 24%) never conformed | Asch (1956) |
| Social | Effect of one dissenting voice in the Asch experiments | When one other person gave the correct answer, conformity dropped to about 5% of trials | Asch (1956) |
| Social | Young people who never had an adult mentor | About 1 in 3 (an estimated 16 million), including about 9 million considered at risk | MENTOR, The Mentoring Effect (2014), nationally representative U.S. survey |
| Social | Postsecondary enrollment among at-risk young people | 45% of those with a mentor vs. 29% of those without. This is a correlation from a survey, not proof that mentoring caused the difference | MENTOR, The Mentoring Effect (2014) |
| Social | In-group favoritism | A meta-analysis of 212 studies found people cooperate more with members of their own group than with outsiders (d = 0.32), and that this reflects favoritism toward the in-group more than hostility toward the out-group | Balliet, Wu, and De Dreu (2014) |
| Social | Partner violence against women | Based on 366 studies covering 2 million women in 161 countries, an estimated 27% of ever-partnered women aged 15 to 49 have experienced physical or sexual violence from a partner, and 13% in the past year. Rates are higher in low-income countries. Childhood abuse and household dysfunction are covered under early-life adversity in the biological key figures | Sardinha et al. (2022) |
| Social | Neighbors' earnings and happiness | In U.S. panel data on 8,944 adults, people whose neighbors earned more reported lower happiness, holding their own income constant. The author found this was not explained by who chose to live where. German data found the opposite for neighbors: once comparisons with coworkers and people of the same sex were accounted for, higher neighborhood income was linked to more happiness, while comparisons with those peers predicted lower wellbeing (Mayraz, Wagner, and Schupp, 2009). Who people compare themselves with appears to matter more than neighbors as such | Luttmer (2005) |
| Social | Partner violence and women's work | Among 1,311 Illinois welfare recipients, recent partner violence was linked to unstable employment over three years, largely through health problems (National Institute of Justice). In Tanzania, women who had been abused earned less than women who had not (World Bank). A Colombian study found the opposite, with partner violence increasing women's employment, possibly as a way to escape (EAFIT seminar abstract). All are observational, so the effect of adult partner violence on achievement is rated C | NIJ, World Bank, EAFIT |
| Social | Trickle-down consumption | Using variation across U.S. states and years, non-rich households exposed to higher top incomes spent a larger share of income, especially on visible goods, reported more financial strain, and lived in states with more personal bankruptcies. Middle-income households might have saved an additional 2.6% to 3.2% of their income by the mid-2000s had top incomes grown at the same rate as median income. The authors judge status-driven spending the most consistent explanation. Other work is mixed: a related study supports such "expenditure cascades" (Frank, Levine, and Dijk, 2014), but a working paper found no effect when comparison groups were defined by census division (Wang, working paper) | Bertrand and Morse (2016) |
| Environmental | Premature deaths, ambient plus household air pollution | 6.7 million per year | WHO |
| Environmental | Premature deaths, ambient air pollution | About 4.2 million | WHO |
| Environmental | Household air pollution deaths, 2021 | 2.9 million (over 309,000 children under 5) | WHO |
| Environmental | IQ loss, blood lead from 2.4 to 30 µg/dL | 6.9 points (1,333 children) | Lanphear et al. (2005) |
| Environmental | Americans with high early-childhood lead exposure | Over 170 million, about 824 million IQ points | McFarland et al. (2022) |
| Environmental | Global lead burden, 2019 | 765 million IQ points lost in children under 5, about 5.5 million adult cardiovascular deaths, over 90% of the harm in low- and middle-income countries, and a cost of about US$6.0 trillion (roughly 6.9% of global GDP) | Larsen and Sánchez-Triana (2023), model estimate with wide uncertainty |
| Environmental | All pollution combined | About 9 million deaths per year, one in six | Fuller et al. (2022) |
| Environmental | Growth in "modern" pollution deaths since 2000 | Over 66% | Fuller et al. (2022) |
| Environmental | Learning lost per 1°F hotter school year, no air conditioning | 1 percent of that year's learning. Hot school days accounted for roughly 5 percent of the racial achievement gap | Park et al. (2020), 10 million students who retook the PSAT |
| Environmental | Average annual temperature at which productivity peaks | About 13°C | Burke et al. (2015) |
| Environmental | Projected cut in global incomes by 2100, unmitigated warming | Roughly 23%. This depends on adaptation assumptions and is debated | Burke et al. (2015) |
| Environmental | Malaria, 2024 | 282 million cases and 610,000 deaths, up from a revised 273 million cases in 2023. About 95% of deaths occurred in the WHO African Region, mostly among children under 5 | WHO World Malaria Report 2025 |
| Environmental | School-aged children in the American South with hookworm | 40% | Rockefeller Sanitary Commission |
| Environmental | Effect of hookworm treatment | Areas with higher infection saw larger gains in enrollment, attendance, literacy, and later income. An independent replication questioned whether these benefits are robust | Bleakley (2007), Roodman (2018) |
| Environmental | Lack safely managed drinking water | 2.1 billion, including 106 million who drink untreated surface water | WHO/UNICEF JMP 2025 |
| Environmental | Lack safely managed sanitation | 3.4 billion, including 354 million who practice open defecation | WHO/UNICEF JMP 2025 |
| Environmental | Planetary boundaries exceeded | 7 of 9: climate change, biosphere integrity, land system change, freshwater use, biogeochemical flows, novel entities, and ocean acidification. Only aerosol loading and stratospheric ozone remain in the safe zone | Planetary Health Check 2025 |
| Environmental | Psychiatric disorder risk, least vs. most childhood green space | Up to 55% higher (correlational) | Engemann et al. (2019) |
| Educational | Learning poverty, low- and middle-income countries | About 70% (57% pre-pandemic) | World Bank and partners (2022) |
| Educational | Learning poverty, Sub-Saharan Africa | About 89% | World Bank and partners (2022) |
| Educational | Learning poverty, Latin America and the Caribbean | Predicted to reach about 80%, up from around 50% before the pandemic | World Bank and partners (2022) |
| Educational | Projected lifetime earnings lost by this generation | US$21 trillion, about 17% of global GDP | World Bank |
| Educational | Children and youth out of school | 273 million in the 2026 estimate, about 1 in 6 of school age and up for seven years in a row. UNESCO's June 2025 estimate was 272 million, and conflict-affected countries add at least 13 million more who are not in the main count | UNESCO (2026, 2025) |
| Educational | Out-of-school rate by level, June 2025 estimate | 11% of primary-age children (78 million), 15% of lower-secondary-age (64 million), and 31% of upper-secondary-age youth (130 million) | UNESCO (2025) |
| Educational | Change in out-of-school numbers since 2015 | Fallen by less than 1% | UNESCO (2025) |
| Educational | Learning lost to COVID-19 disruption | About 35% of a normal school year. Losses were stable over time, larger for lower socioeconomic backgrounds and poorer countries, and larger in math than in reading | Betthäuser et al. (2023), 42 studies, 15 countries |
| Educational | Bottom-5% teacher replaced by average, per classroom | About US$250,000 lifetime income. A published comment found these long-run estimates sensitive to modeling choices, so the figure is uncertain | Chetty, Friedman, and Rockoff (2014), Rothstein (2017) |
| Educational | TaRL language gains | 0.15 SD (Haryana), 0.70 SD (Uttar Pradesh) | Banerjee et al. (2016), J-PAL |
| Educational | High-stakes exams and pollution, Israel | Israeli students scored lower on matriculation exams taken on days with more fine-particle pollution, and the same students had lower post-secondary attainment and earnings years later. Later studies found similar exam-day effects of pollution on China's College English Test and of heat on New York City exit exams, where hot exam days lowered scores by up to 13% of a standard deviation and reduced high school graduation | Ebenstein, Lavy, and Roth (2016), Yao et al. (2023), Park (2022) |
| Technological | Internet users and people offline | 6 billion use the internet and 2.2 billion remain offline. 96% of those offline live in low- and middle-income countries | ITU Facts and Figures 2025 |
| Technological | Share online by group, 2025 | High-income countries 94%, low-income countries 23%, urban areas 85%, rural areas 58%, men 77%, women 71% | ITU (2025) |
| Technological | 5G coverage, high-income vs. low-income countries | 84% vs. 4% | ITU (2025) |
| Technological | People without basic electricity, 2024 | About 655 million, leaving about 92% of the world with basic access. 89 million people gained access that year, but population growth meant the total fell by only about 11 million. About 86% of those without power (563 million people) live in sub-Saharan Africa | Tracking SDG7 (2026) |
| Technological | People lacking clean cooking | About 2 billion | Tracking SDG7 (2026) |
| Technological | Average lag from invention to adoption, 15 technologies in 166 countries over two centuries | 45 years, with wide variation. Newer technologies have been adopted faster than older ones | Comin and Hobijn (2010) |
| Technological | Income differences accounted for by differences in technology adoption | At least 25% of per capita income differences | Comin and Hobijn (2010) |
| Technological | One Laptop per Child, Peru (318 rural schools) | Computers per student rose from 0.12 to 1.18, with no evidence of effects on math or language test scores after 15 months | Cristia et al. (2017) |
| Technological | One Laptop per Child, long-term follow-up | No significant effects on academic performance, school completion, or university enrollment, and some evidence of slower grade progression. Computer skills improved, but teachers' digital skills did not, and classroom computer use was low | Cueto et al. (2025) |
| Technological | Mindspark gains after 4.5 months | 0.37 SD math, 0.23 SD Hindi | Muralidharan et al. (2019) |
| Technological | Spread of true and false news on Twitter, 2006 to 2017 | About 126,000 verified stories studied. False news spread significantly farther, faster, deeper, and more broadly than true news in every category | Vosoughi et al. (2018) |
| Technological | Digital technology use and adolescent wellbeing (debated) | Three datasets totaling 355,358 adolescents. The association was negative but small, explaining at most 0.4% of the variation in wellbeing | Orben and Przybylski (2019) |
| Technological | Robots: employment and wage effect per robot per 1,000 workers | -0.2 percentage points, -0.42% | Acemoglu and Restrepo (2020) |