Introduced in 1971, a corporate income tax on commercial enterprises other than individual traders remains the only tax in the country. Rates range from 5% to 50%. Legislation in 1981 reduced the maximum tax rate to 15% for companies in which Omanis hold at least a 51% equity, and to 20% for companies in which the Omani equity is between 35% and 50%. Companies engaged in agriculture, fishing and any other essential activity deemed by the government are exempt from income taxes. Oman has a comprehensive double taxation treaty with France.