The Fertility Rate of a Country

Multi Ethnic Babies Sitting on White.
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The term total fertility rate describes the total number of children the average woman in a population is likely to have based on her birth rate at any given time—this number is meant to project the number of children a woman will have throughout her lifetime.

Total fertility rates tend to differ greatly by country. Developing countries in Africa, for example, usually see a total fertility rate of around six children per woman. Eastern European and highly developed Asian countries, on the other hand, can expect closer to one child per woman. Fertility rates along with replacement rates are an excellent indicator of whether a population will experience growth or decline.

Replacement Rate

The concept of replacement rate is directly associated with that of fertility rate. Replacement rate is the number of children a woman needs to have in order to maintain the current population levels of her family, or what is known as zero population growth. In other words, replacement-level fertility exactly replaces a woman and her partner for a net loss of zero when she and the father of her children die.

In developed countries, a replacement rate of about 2.1 is necessary to sustain a population. Replacement cannot occur if a child does not reach maturity and have their own offspring, so the extra 0.1 children per woman is built in as a 5% buffer. This accounts for the death of a child or a child that chooses not to or is unable to have children of their own. In less developed countries, the replacement rate is around 2.3 due to higher childhood and adult mortality rates.

World Fertility Rates

With fertility rates being such a useful tool for reading the health of a population, researchers often study them closely. They are keeping their eyes on the fertility rates of a few countries, in particular, to predict what is likely to be considerable population fluctuation. Some nations can expect their numbers to soar in the coming years. Mali with a fertility rate of 6.01 and Niger with a fertility rate of 6.49 as of 2017, for example, will grow exponentially in the next few years unless growth rates and total fertility rates suddenly plummet.

Mali's population in 2017 was approximately 18.5 million, up from 12 million just a decade prior. If Mali's high total fertility rate per woman remains the same or even continues to grow, its population will essentially explode. Mali's 2017 growth rate of 3.02 was the result of fertility rates doubling in only 23 years. Other countries with high total fertility rates include Angola at 6.16, Somalia at 5.8, Zambia at 5.63, Malawi at 5.49, Afghanistan at 5.12, and Mozambique at 5.08.

On the other hand, more than 70 countries had a total fertility rate of less than two in 2017. Without widescale immigration or an increase in total fertility rates, these nations will have declining populations over the next few decades. Both developed and developing countries can face negative population growth. Examples of countries with low fertility rates are Singapore at 0.83, Macau at 0.95, Lithuania at 1.59, the Czech Republic at 1.45, Japan at 1.41, and Canada at 1.6.

U.S. Fertility Rates

Perhaps surprisingly, the U.S. fertility rate is below replacement level. The total fertility rate for the United States in 2019 was calculated at 1.7 and the total fertility rate for the world was 2.4, down from 2.8 in 2002 and 5.0 in 1965. This steadily decreasing fertility rate spells decreasing populations in the U.S. China's defunct one-child policy contributed to the country's current fertility rate of 1.62.

Different cultural groups within a country can exhibit very different total fertility rates. In the United States, for example, when the country's overall fertility rate was 1.82 in 2016, the total fertility rate was 2.09 for Hispanics, 1.83 for African Americans, 1.69 for Asians, and 1.72 for white Americans, the largest ethnic group.