The Countries With The Fastest Growing Populations

5. Tanzania
> Population Growth 2011-2050: 92 million
> 2011 Population: 46.2 million (30th largest)
> Pct. Increase: +199% (5th greatest)
> Pct. of Population < 15: 45% (15th greatest)
> GDP per Capita: $1,491

Tanzania’s current population of 46.2 million is expected to triple by 2050. This is going to cause the East African country’s population density, which is currently relatively low, to skyrocket. The country’s area is roughly 350,000 square miles, approximately twice the size of California. Tanzania is expected to have over 138 million people by 2050. As of 2009, 5.6% of the country’s population lived with HIV/AIDS, the twelfth highest recorded rate in the world. Life expectancy at birth is just 57 years.

4. United States
> Population Growth 2011-2050: 111 million
> 2011 Population: 311.7 (3rd largest)
> Pct. Increase: +36% (94th greatest)
> Pct. of Population < 15: 20% (150th greatest)
> GDP per Capita: $48,665

The United States is an outlier among the countries set to add the most people for many reasons. It is the only developed nation on this list, with most European populations remaining flat, and some actually losing citizens by 2050. Over the next four decades, the world is expected to add 2.6 billion people. The developed world will only account for 90 million of the projected 2.6 billion population increase by 2050. The United States is the only country that keeps the developed world growing – it is projected to add 111 million people.

3. Pakistan
> Population Growth 2011-2050: 137 million
> 2011 Population: 176.9 (6th largest)
> Pct. Increase: +77.6% (55th greatest)
> Pct. of Population < 15: 36% (60th greatest)
> GDP per Capita: $2,851

Pakistan is slightly smaller than Tanzania, or nearly twice the area of California. Despite its relatively small size, the country has the sixth largest population in the world. Only 27% of women between the ages of 15 and 49 use contraception, and that percentage drops to 19% for women using modern methods of contraception. In the United States, those numbers are 79% for all methods and 73% for modern methods. Additionally, the percentage of the population that is under 15 years of age is nine times the percentage that is 65 or older.

2. Nigeria
> Population Growth 2011-2050: 271 million
> 2011 Population: 162.3 (7th largest)
> Pct. Increase: +167% (7th greatest)
> Pct. of Population < 15:  43% (25th greatest)
> GDP per Capita: $2,546

Nigeria currently has the 7th largest population in the world. By 2050, the United Nations projects it will rise to 3rd, passing Brazil and the United States. Nigeria will nearly triple to 433 million people, adding the equivalent of the 30 most populous states in the U.S. Nigeria suffers from poor access to safe drinking water – just 42% of the rural population has access to clean water. As is the case in most of sub-Saharan Africa, AIDS is a serious problem in the country, as is infant mortality. Each year, 17 out of every 1,000 Nigerians die. This is the second highest rate in the world. However, low use of birth control and high fertility have counteracted these conditions to produce skyrocketing population growth.

1. India
> Population Growth 2011-2050: 450 million
> 2011 Population: 1,241.3 (2nd largest)
> Pct. Increase: +36% (93rd greatest)
> Pct. of Population < 15: 33% (77th greatest)
> GDP per Capita: $3,608

India, the world’s second largest country by population, currently accounts for just under 17.5% of the world’s population and shows no signs of slowing down. By 2025, the country is projected to surpass China as the most populous in the world — a place India is expected to hold through 2050. By that point, issues of overcrowding will be significant. Within four decades, the population will swell to 1.7 billion.

Michael B. Sauter