Not surprisingly, the largest countries in the world in terms of population are China and India, with both countries now having populations of well over a billion. The United States comes in third with just under 325 million residents. The BRIC countries (Brazil, Russia, India and China), generally regarded as the four major emerging economies expected to dominate in the 21st century, are all in the top ten most populous countries, indicating how important the sheer size of their populations are to their economic expansion.
However, a number of countries considered by the International Monetary Fund to be developing countries (that is, having not achieved a high degree of industrialization relative to their populations, and where the population typically has a medium to low standard of living) also have sizeable populations, including Nigeria (over 190 million), Bangladesh (almost 165 million) and Mexico (around 129 million), demonstrating that the issues affecting developing nations span multiple continents.
It is notable that a number of the largest economies in the world have smaller populations, particularly in Europe. The United Kingdom, Germany, France, and Italy are all among the top ten largest economies and all have populations of under 100 million. Their numbers range from 82 million (Germany) to just under 60 million (Italy).
Furthermore, several extremely small countries, such as Monaco, Luxembourg, and the Cayman Islands - all with fewer than a million residents - play a much larger role in the financial world than their population numbers would suggest. In contrast, Canada, which is also a major economic player and one of the largest countries in the world by landmass, has a relatively small population for its size, with around 36.5 million residents.