Citigroup Inc. or citi is an American multinational investment bank and financial services corporation headquartered in New York City. The company was formed by the merger of banking giant Citicorp and financial conglomerate Travelers Group in 1998. Citigroup is the third largest banking institution in the United States; alongside JPMorgan Chase, Bank of America, and Wells Fargo, it is one of the Big Four banking institutions of the United States. Citigroup is ranked 30th on the Fortune 500 as of 2019. Citigroup has over 200 million customer accounts and does business in more than 160 countries. It has 204,000 employees.