which provides the following benefits: contribution to economic diversification by providing a window for free trade as well as stimulating the establishment of support services; administration of a regime that imports, exports, and warehouses general merchandise; adequate storage facilities and other infrastructure to cater for effective operation of trade; and creation of an efficient management system for effective re-exportation of goods. The island's manufacturing sector is limited mainly to import substitution industries, such as cigarettes, shoes, and processed agricultural products. In 1992, the government designated two export-producing zones and encouraged the development of offshore financial services. Zanzibar still imports much of its staple requirements, petroleum products, and manufactured articles. There is also a possibility of oil availability in Zanzibar on the island of Pemba, and efforts have been made by the Tanzanian government and Zanzibar revolutionary government to exploit what could be one of the most significant discoveries in recent memory. Oil would help boost the economy of Zanzibar, but there have been disagreements about dividends between the Tanzanian mainland and Zanzibar, the latter claiming the oil should be excluded in Union matters. In 2007, a Norwegian consultancy firm went to Zanzibar to determine how the region could develop its oil potential. The firm recommended that Zanzibar follow economist Hernando de Soto Polar's ideas about the formalization of property rights for persons living on ancestral land for which they probably do not have a legal deed. Tourism Energy The energy sector in Zanzibar consists of unreliable electric power, petroleum and petroleum products; it is also supplemented by firewood and its related products. Coal and gas are rarely used for either domestic or industrial purposes. Unguja (Zanzibar Island) gets most of its electric power from mainland Tanzania through a 39-kilometer, 100-megawatt submarine cable from Ras Kiromoni (near Dar es Salaam) to Ras Fumba on Unguja. The laying of the cable was begun on 10 October 2012 by the Viscas Corporation of Japan and was funded by a US$28.1 million grant from the United States through the Millennium Challenge Corporation.132kV Sabmarine Cable – Zanzibar Iterconnector at Ras Kiromoni and Ras Fumba , Featured Project, Salem Construction, Ltd. The cable became operational on 13 April 2013. The previous 45-megawatt cable, which was seldom-maintained, was completed by Norway in 1980. Since May 2010, Pemba Island has had a , 25-megawatt, subsea electrical link directly to mainland Tanzania. The cable project was financed through a