Agriculture was the main source of growth and foreign exchange until 1978 when oil production replaced it as the cornerstone of growth for the formal economy. In 2001, agriculture contributed 43% to GDP. Agricultural development and productivity declined from neglect during the oil boom years of the early 1980s. Agriculture was the principal occupation of 62% of the economically active population in 1999, although only about 15% of the land was arable. The most important cash crops are cocoa, coffee, cotton, bananas, rubber, palm oil and kernels, and peanuts. The main food crops are plantains, cassava, corn, millet, and sugarcane. Palm oil production has shown signs of strength, but the product is not marketed internationally. Cameroon bananas are sold internationally, and the sector was reorganized and privatized in 1987. Similarly, rubber output has grown in spite of Asian competition.
Cameroon is among the world's largest cocoa producers; 150,000 tons of cocoa beans were produced in 1999. Two types of coffee, robusta and arabica, are grown; production was 90,000 tons in 2001–2002. About 85,000 hectares (210,000 acres) are allocated to cotton plantations. Some cotton is exported, while the remainder is processed by local textile plants. Total cotton output was 79,000 tons in 1999. Bananas are grown mainly in the southwest; 1999 estimated production was 990,000 tons. The output of rubber, also grown in the southwest, was 54,000 tons in 1999. Estimated production in 1999 of palm kernels and oil was 58,000 and 160,000 tons, respectively. For peanuts (in the shell) the figure was 170,000 tons. Small amounts of tobacco, tea, and pineapples are also grown.
Estimated 1999 production of food crops was as follows: sugarcane, 1,350,000 tons; cassava, 1,500,000 tons; plantains, 1,000,000 tons; corn, 600,000 tons; millet, 71,000 tons; yams, 130,000 tons; sweet potatoes, 220,000 tons; potatoes, 49,000 tons; dry beans, 95,000 tons; and rice, 65,000 tons.