Seoul, officially the Seoul Special City, is the capital and largest metropolis of South Korea. Seoul has a population of 9.7 million people, and forms the heart of the Seoul Capital Area with the surrounding Incheon metropolis and Gyeonggi province. Seoul was the world's 4th largest metropolitan economy in 2014 after Tokyo, New York City and Los Angeles. In 2017, the cost of living in Seoul was ranked the 6th highest globally.