maintain proximity to the federal government. The largest U.S. government agencies located in or near the city are: (1) the United States Department of Defense headquartered in the Pentagon in Arlington County, (2) the United States Postal Service, (3) the United States Department of Veterans Affairs, (4) the United States Department of Homeland Security, and (5) the United States Department of Justice. Diplomacy and global finance Washington, D.C. hosts more than 175 embassies, ambassador’s residences and international cultural centers. Embassy Row is the informal name given to a stretch of Massachusetts Avenue that is occupied by many of the city's foreign embassies. Washington, D.C. is one of the most diverse cities in the world. In 2008, the foreign diplomatic corps in the city employed approximately 10,000 people and contributed an estimated $400 million annually to the local economy. Many prominent global financial and diplomatic institutions are headquartered in the city, including the World Bank, the International Monetary Fund (IMF), the Organization of American States, the Inter-American Development Bank, and the Pan American Health Organization. These institutions seek to use money lending and other financial and economic tools to improve the state of countries' economy and development. The Federal Reserve, which is the central bank in the U.S., is located on Constitution Avenue. Commonly called The Fed, its policies are made by the members of the Federal Reserve Board of Governors. Through monetary policy, the Board adjusts various interest rates in the U.S., which heavily impacts the U.S. economy and economies for countries across the world. Because of the power of the U.S. dollar, the actions of the Board are monitored closely by political, economic, and diplomatic leaders around the world. Research and non-profit organizations Washington, D.C. is a leading center for national and international research organizations, especially think tanks that engage on public policy. Several of the nation's largest and most cited think tanks are headquartered in the city, including the Carnegie Endowment for International Peace, Center for Strategic and International Studies, Peterson Institute for International Economics, The Heritage Foundation, Urban Institute, and others. As of 2020, 8% of the country's think tanks are headquartered in Washington, D.C. Many non-think tanks are also leading research centers, such as the MedStar Washington Hospital Center and the Children's National Medical Center. The city is home to many non-profit organizations that engage with issues of domestic and global importance by conducting advanced research,