Associated with total fertility rate is the concept of replacement rate. The replacement rate is the number of children each woman needs to have to maintain current population levels or what is known as zero population growth for her and her partner.
In developed countries, the necessary replacement rate is about 2.1. Since replacement can not occur if a child does not grow to maturity and have their own offspring, the need for the extra .1 child (a 5% buffer) per woman is due to the potential for death and those who choose or are unable to have children. In less developed countries, the replacement rate is around 2.3 due to higher childhood and adult death rates.
Nonetheless, with total fertility rates of 7.38 in Mali and 7.37 in Niger (as of mid-2007), the resultant growth in these countries' populations is expected to be phenomenal over the next few years, unless growth rates and total fertility rates drop. For example, Mali's 2007 population is approximately 12 million. With its high total fertility rate per woman, Mali is expected to grow to more than 15 million (a 3 million or 25% increase) by 2015! Mali's 2007 growth rate of 2.7 means a doubling time of just 26 years. Other countries with high total fertility rates include Afghanistan at 6.64, Yemen at 6.49, and Samoa at 4.21.
On the other hand, more than 70 countries have (as of mid-2007) a total fertility rate of less than 2! Without immigration or an increase in total fertility rates, all of these countries will have declining populations over the next few decades. Some of the lowest total fertility rates include developed as well as developing countries alike. For example: Singapore at 1.07, Lithuania at 1.21, Czech Republic at 1.22, Japan at 1.23, and even Canada at 1.61 (the European Union as a whole has a very low total fertility rate of 1.5!)
The total fertility rate for the United States is just below replacement value at 2.09 and the total fertility rate for the world is 2.59, down from 2.8 in 2002 and 5.0 in 1965. China's one-child policy definitely shows in the country's total low fertility rate of 1.75.
Different cultural groups within a country can exhibit different total fertility rates. In the United States, for example, when the country's total fertility rate was 2.1, the total fertility rate was 3.0 for Hispanics, 2.2 for African Americans, and the below replacement of 1.9 for Asian and Pacific Islanders.*
As you can see, total fertility rates are closely tied to growth rates for countries and can be an excellent indicator of future population growth or decline for a country or for a population within a country.
The CIA World Factbook provides an up-to-date ranked list of total fertility rates for countries and other entities worldwide. The listing is the source of the data for this article.
*Source: Getis, Getis, and Fellmann, Introduction to Geography. 2004, McGraw Hill.