Gabon's economy is dominated by oil. The combination of a small population and plentiful petroleum resources has given Gabon one of the highest incomes per capita in sub-Saharan Africa. Gabon depended on timber and manganese until oil was discovered in the early 1970s. The economy is highly dependent on extraction of abundant primary materials. After oil, logging and manganese mining are the other major sectors. Gabon's main exports are crude petroleum, forest products, manganese and uranium ores, and cocoa; the principal imports are machinery and equipment, foodstuffs, chemicals, and construction materials. The leading trade partners are the United States and France.