Although manganese mining halted in 1978, there was an agreement in 2006 to export manganese already mined but not yet exported. The country has no known petroleum deposits. A small light-industry sector caters to the local market. Tax revenues come mainly from import duties and a 15% VAT on goods and services. Economic development is hindered by dependence on relatively few commodity exports, vulnerability to natural disasters, and long distances between constituent islands and from main markets.