Gender Inequality: Today, with higher female participation and lower wage differentials, the loss is 7% of GDP and by 2050 it is projected to fall to 4%. In 1900 we were essentially excluding almost half the world’s population from production. The loss was at least 17% of global GDP
Malnutrition: Hunger, one of humanity’s oldest scourges, has relented. The cost of malnutrition has almost halved from 11% of GDP in 1900 to 6% today, and should fall to 5% in 2050.
Human Health: The cost of poor health at the outset of the 20th century was a phenomenal 32% of global GDP. Today, it is down to about 11%, and by 2050 will have halved again.
Education: Illiteracy today afflicts 23.6% of the world’s population. Yet, in 1900 perhaps 70% were illiterate. In 1900, the cost of not having literacy was 12.3% GDP. Today, that number is close to 7%. By 2050, it is estimated illiteracy will reach about 12% and the cost will have dwindled to just 3.8% of GDP.
Climate Change: Climate change is real and man-made. It will come as a big surprise that climate change from 1900 to 2025 has mostly been a net benefit, rising to increase welfare about 1.5% of GDP per year. After year 2070, global warming will become a net cost to the world, justifying cost-effective climate action. The biggest environmental problem in the world is, perhaps surprisingly, air pollution. Over the 20th century, 260 million died from indoor air pollution in the Third World – about twice the toll in all the century’s wars.