Africa. By 2050, Africa is projected to increase to 2.4 billion from 1.1 billion today making it the region with the largest population growth. But this projection should be treated very cautiously, because it assumes that birth rates will decline smoothly in all African countries in much the same way as birth rates declined in other regions. And that assumption, in turn, assumes that the effective use of family planning will spread in Africa. In most countries, declines in birth rates have been very slow or even nonexistent. And even with declining birth rates, sub-Saharan Africa's population will continue to grow at a fairly rapid pace after 2050 because there are so many young people
Asia. Asia is home to 60% of global population. China and India account for more than half of Asia's total population. China's total fertility rate is a very low 1.5 children per woman. Should China become concerned about population aging and relax its strict "one-child" policy, projections of China's population may have to be raised. In India, the TFR has fallen from about 5.5 children in the past to 2.4 today. But doubts about the future course of the birth rate in India's heavily populated and impoverished northern states makes projections challenging. Nonetheless, India is projected to pass China in population size in about 15 years, becoming the world's most populous country, around 1.5 billion people.
Latin America/Caribbean. Population growth has been in slow decline in this region, largely due to a lower birth rate in Brazil and Mexico, which account for more than half of the region's population. In Brazil, women average 1.8 children, while in Mexico the average is about 2.2. Among developing regions, Latin America/Caribbean has the highest prevalence of family planning at 75% for all methods and 68% for modern methods among married women. The region's population is projected to increase from 606 million today to 780 million in 2050. Three-quarters of a million migrants (on a net basis) leave the region for North America and Europe each year.
North America. The United States and Canada have rather low TFRs: Canada at 1.6 and the United States at 1.9. In the U.S., fertility declined during the recent economic recession, a decline that was especially sharp among Hispanics. Immigration is a significant engine of population growth in both countries.
Europe. Europe's birth rate has plummeted to an unexpectedly low level in the past few decades. Europe's population of 740 million is projected to decrease to 726 million by 2050, but even that lower number depends on whether immigration helps to stall a more-rapid decline. Today, women in Europe average only 1.6 children, compared to 2.6 in 1960. This low fertility has created unprecedented aging. In Europe, only 16% of the population is below age 15. Compare that to 41% in Africa and 25% in Asia. Europe's population ages 65+ is projected to rise to 27% by 2050.
Oceania. In Australia and New Zealand, continued growth from higher birth rates and immigration are expected. Australia's TFR is 1.9; New Zealand's, 2.0. Australia's population of 23 million is expected to increase to 34 million by 2050; New Zealand's population will increase from 5 million to just under 6 million.