Coming on the heels of a growing concern about Nigeria’s rising population, a new study by the International Monetary Fund (IMF) highlights “new fertility facts” that are challenging old theories on the relationship between childbearing, years of education and income level.
It points out low-income countries, such as Nigeria and other African countries, as the only places where the negative relationship between income and fertility rate still holds sway.
The Population Division of the United Nations Department of Economics and Social Affairs said Nigeria would become the world’s fourth most populous country in the next 28 years with a population of 375 million.
The projection comes with a foreboding of escalation of the social ills of overpopulation including unemployment, food crisis and crime rates.
Nigeria’s growth had buckled under a fast-growing population in recent times until last year when the gross domestic product (GDP) got an upper hand at 3.6 per cent compared with the average population growth of 2.6 per cent in the past decade. Except the country acts fast, experts are worried about the dire consequence of overpopulation even as the country is estimated to have hit 216 million.
While Nigeria is worried about bloated size, the IMF study entitled, ‘The New Economics of Fertility’ raises concern about emerging ultralow fertility in high-income countries like Germany, Italy, Japan and Spain where the fertility rate is about 1.5 in the past two decades.
The rate, the researchers are worried, is below the average of “just over two children per woman needed to maintain a stable population size.”
The study published as an analytical series, yesterday, reviews established labour economics theories such as the quantity-quality trade-off, which suggests that as parents get richer, they incur costly investments in their children.
“This investment is costly, so parents choose to have fewer children as incomes rise. Historically, fertility and GDP per capita are strongly negatively related, both across countries and over time,” it observes.
It also recalls another theoretical explanation for low fertility among high-income individuals, saying: “As wages increase, devoting time to childcare – time that could otherwise be spent working – becomes more costly for parents, and especially for mothers. The result is a decline in fertility and greater female labour force participation. There is historically a strong negative association between female labour force participation and fertility over time and across countries.”
The report, however, argues that new data have proved that the theories are losing universal appeal. It contends, notwithstanding, that the negative income-fertility relationship is still predominantly true in low-income countries such as sub-Saharan Africa (SSA).
“It has largely disappeared both within and across high-income countries. The same is true for the relationship between fertility and female labor force participation. In a recent survey, we outline these new empirical regularities and discuss the key factors that explain fertility outcomes in recent decades.
“For a long time, high per capita income in a country reliably indicated low fertility. In 1980, fertility was still well above two children per woman in poorer countries, such as Portugal and Spain, but just 20 years later, fertility in the same set of countries had changed substantially. In fact, in 2000 the United States, the second-richest country in the sample, exhibited the highest fertility rate,” the research discloses.
It also reports changing fertility patterns across families in high-income countries (such as France, Germany and the United States). In those countries, it states, the negative relationship between female education and fertility, which is consistent with higher wages increasing the opportunity cost of raising children, is becoming weaker.
“This negative relationship is weaker for US women of recent birth cohorts. Although highly educated women with more than 16 years of schooling had the lowest fertility rate in 1980, this no longer holds true in 2019,” it reveals.