David Lam

The UN projects that world population will peak at 10.3 billion in 2084, a 2.1 billion increase from 2024. Can the world provide food, water, and other resources to 10.3 billion people? How will additional population exacerbate resource challenges and worsen climate change? This paper analyzes these questions by looking at the last 60 years and by simulating the future impact of population growth and rising incomes on food, water, energy, and CO₂ emissions. Looking back, food production has increased faster than the population in all regions, and we have not experienced significant shortages in nonrenewable resources. The history of water and CO₂ emissions is less encouraging, however, with declining water levels in many aquifers and global warming threatening to undermine progress in all areas. Looking forward, population growth will be concentrated in poor countries, while rich countries, with higher consumption levels and emissions, will experience population decline. Population growth is projected to significantly increase demand for food and water in coming decades but is projected to have only modest impacts on energy and CO₂, with population decline in high‐emission higher income countries more than offsetting the impact of population growth in low‐emission lower‐income countries.

Between 1960 and 2011, world population grew from 3 to 7 billion, an unprecedented rate of population growth that will never be seen again. In spite of the addition of 4 billion people in just 51 years, the world experienced some of the biggest improvements in living standards in human history, with declines in poverty and improvements in food production per capita in all major regions. This paper looks at the period since 2011, during which the world added another billion people. Progress has continued in many areas, with food production continuing to grow faster than population and with continued declines in the proportion of the population in poverty in all regions. Not all trends are positive, however. Progress in food production has slowed, with recent declines in food production per capita in Africa. Prices of food and other commodities have recently hit historic highs. Climate change is a challenge to progress in combatting hunger and poverty, especially in Africa. While climate change will make it harder to meet the needs of Africa’s continued population growth in this century, the paper shows that the countries with the highest population growth account for a very small share of global CO₂ emissions. The record of the last six decades suggests that progress can be made to reduce poverty and hunger, even while world population continues to grow, but continued progress will require solutions to climate change that mainly target high-income and middle-income countries.

This paper argues that distributions of spousal earnings gaps provide no identifying information for the male breadwinner norm, nor such a norm’s consequences for gender inequality. First, we show that simple marital matching models—without norm-related assumptions—closely replicate U.S. distributions of wife-husband earnings gaps. Second, we show that the discontinuity in this distribution as wives start to out-earn husbands reflects not breadwinner norms, but rather a point mass of equal-earning couples. We conclude by arguing that the point mass may also threaten other tests of the male breadwinner hypothesis, and proposing several robustness checks that future research should utilize.

Human capital models imply that both the distribution of education and returns to education affect earnings inequality. Decomposition of these ‘quantity’ and ‘price’ components have been important in understanding changes in earnings inequality in developed and developing countries. This paper provides theoretical and empirical analysis of the interactions between schooling inequality, returns to schooling and earnings inequality. We focus on two main questions. What is the relationship between inequality in schooling and inequality in earnings? How do changes in returns to schooling affect earnings inequality when returns differ by schooling level? We derive new analytical results that are used to guide empirical analysis of changes in earnings inequality in Brazil and South Africa. While both countries have had declines in schooling inequality, only Brazil has translated those into declines in earnings inequality. In South Africa, rising returns to schooling at the top level have offset equalizing changes in the schooling distribution.

This chapter examines the status of education in post-apartheid Africa. It discusses trends in educational attainment; the racial gap in education as youth progress through school; grade repetition; academic performance; and school funding and school fees.

The release of the National Income Dynamics Study Wave 2 provides the first nationally representative longitudinal data collected in South Africa, making it possible to study transitions in and out of school, across grades and into work, in ways not previously possible. We illustrate the high levels of grade repetition evident in South African schools and show how school completion presents a significant hurdle with very few youth successfully matriculating. Exit from school does not offer any advantages as most youth find themselves idle once they have left school. Our regression analysis investigates correlates of school dropout and shows that falling behind is a key determinant of school dropout, even after controlling for school quality and socio-economic status. Those behind but attending higher quality schools are partially protected from dropping out. Some evidence that credit constraints may be related to dropout is found, especially among males.