United States Population 2015

According to the US Census Bureau's population clock, the estimated 2015 United States population (July 2015) is over 321.3 million. This differs a bit from the 325.1 million estimated by the United Nations.

By population, the United States of America is the third largest country in the world, a long way behind China (1.4 billion) and India (1.28 billion). Its most populous states are California (39 million) and Texas (27.2 million), and its most populous city is New York City (8.2 million).

Largest state in the United States

The largest state in the USA by population is California, which is estimated to be home to just over 39 million people. If California was a country, it would be the 36th most populous in the world, slightly larger than Poland. Its economy would be the eighth largest economy in the world, with roughly the same GDP as Italy, a European country of 61 million people. Interestingly, though, although California is the largest state in the United States of America, it isn't the largest state in the continent of North America - that honor goes to Brazil's state of Sao Paulo.

Largest city in the United States

The largest city in the USA is, of course, New York City. The city's population is estimated at an impressive 8.3 million, which makes New York City larger than the second and third most populous cities in the United States (Los Angeles and Chicago) combined.

For much of the early 20th century, New York City was the largest city in the world. The stunning growth of cities elsewhere in the world means that today, New York is only the world's 19th largest city, sandwiched between Bangalore in India and Dongguan in China. It is, however, the world's second largest city by GDP - its nominal GDP of $1.28 trillion puts it second only to the Japanese city of Tokyo.

United States Census 2010

The United States census is held once every ten years, to count the number of people in the country and find out basic information about them - for example, age, sex and race. The last census was held in 2010, and the next census will be held in 2020.

The information collected in the census is used for many purposes. The first purpose is to ensure that each seat in Congress represents roughly the same amount of people. Take a look at this video to see how Congressional seats are apportioned:

Population Data via United Nations WPP

United States Population Growth

High levels of immigration combined with a healthy birth rate mean that, in contrast to many other developed countries, the US population continues to grow at a steady rate, increasing at around 0.9% each year.

Data Sources
  1. World Population Prospects - Global demographic estimates and projections by the United Nations
  2. US Census Bureau - US Population Clock
  3. World Happiness Report