Europe is the world's second-smallest continent by surface area, covering about 10,180,000 square kilometres (3,930,000 sq mi) or 2% of the Earth's surface and about 6.8% of its land area. Of Europe's approximately 50 states, Russia is the largest by both area and population, while Vatican City is the smallest. Europe is the third-most populous continent after Asia and Africa, with a population of 731 million or about 11% of the world's population. However, according to the United Nations (medium estimate), Europe's share may fall to about 7% by 2050. In 1900, Europe's share of the world's population was 25%.
