According to statistics from the International Monetary Fund (IMF), Tonga has had a negative trade balance since 1975. In 1975, Tonga's imports totaled $17 million and its exports $6 million. By 1998, according to the CIA World Factbook 2000 , imports had risen to $69 million and exports to $8 million. This illustrates Tonga's very narrow export base, as it relies mainly on squash and fish, with small contributions from other agricultural and manufacturing products. Since squash is the most valuable export and the total production goes to Japan to be used in soups and various food products, that country accounts for more than 40 percent of Tonga's exports. The United States and New Zealand are the other significant export destinations, importing fish and small agricultural and manufacturing products respectively.
The most important imports into Tonga are foodstuffs, machines, and transport equipment. New Zealand is the most important source of foodstuffs and of some manufactures and is the source of about 35 percent of all imports. The next most important import sources are Australia, the United States, and Fiji.
The large negative trade balance is offset by other international transfers. Tourism contributes some international income, and there is potential for expansion in this sector. At the household level, the most important source of income is remittances from relatives living overseas, particularly in New Zealand, the United States and Australia. At the government level, international aid helps to counterbalance the large imbalance in trade.