Foreign trade of the United States comprises the international imports and exports of the United States. The country is among the top three global importers and exporters. The regulation of trade is constitutionally vested in the United States Congress. After the Great Depression, the country emerged as among the most significant global trade policy-makers, and it is now a partner to a number of international trade agreements, including the General Agreement on Tariffs and Trade (GATT) and the World Trade Organization (WTO). Gross U.S. assets held by foreigners were $16.3 trillion as of the end of 2006 (over 100% of GDP).