in 1999, and its application for full membership was under negotiation as of December 2006. Foreign trade Imports totaled an estimated US$4.7 billion in 2005 and are projected to increase to US$5 billion in 2006 and to US$5.4 billion in 2007. Yemen is a net importer of all major categories of products except fuels. Principal imports are machinery and transport equipment, food and livestock, and processed materials. According to the United Nations, Yemen imports more than 75 percent of its main dietary staple—wheat. The principal source of Yemen's imports in 2005 was the United Arab Emirates (13.4 percent of total imports); the bulk of these imports are actually re-exports from the United States and Kuwait. Yemen received 10.6 percent of its total imports from Saudi Arabia and 9 percent from China. In 2005 Yemen's exports totaled US$6.4 billion. Exports are expected to increase to reach a record US$8.6 billion in 2006 as a result of strong oil revenues. Petroleum is Yemen's main export, accounting for 92 percent of total exports in 2004 and 87 percent in 2005. Yemen's non-oil exports are primarily agricultural products, mainly fish and fish products, vegetables, and fruits. In 2005 Asia was the most important market for Yemen's exports, primarily China (37.3 percent of total exports), Thailand, and Japan. Chile was also a primary export market (19.6 percent of total exports). Yemen's import and export values have increased and decreased dramatically in the past 10 years owing to shifts in global oil prices. As a result, the country's trade balance has fluctuated significantly from a deficit of almost US$800 million in 1998 to a surplus of US$1 billion in 2000. Rising oil prices resulted in a surplus of US$817 million in 2004 and a surplus of US$1.7 billion in 2005. In recent years, Yemen has reported increasing non-merchandise deficits. These deficits have, however, been offset by record export earnings, which have resulted in large enough trade surpluses to keep the current account in surplus—US$175.7 million in 2003, US$524.6 million in 2004, and US$633.1 million (about 4 percent of gross domestic product) in 2005. External debt In 1990 the newly unified Republic of Yemen inherited an unsustainable debt burden amounting to roughly 106 percent of gross domestic product. Debt rescheduling by the Paris Club creditor countries in the 1990s coupled with assistance from the World Bank's International Development Agency resulted in a drop in Yemen's debt stock