Citizens of Brunei pay no income taxes and are the beneficiaries of generous welfare subsidies. However, Chinese, who make up an estimated 16% of the population, are excluded from citizenship, and these benefits. They are either stateless or hold British protected persons passports. Only corporations are subject to taxation. Taxation on petroleum income is subject to special legal provisions, dating from 1963. Companies pay a 30% tax on earnings. There is a double-taxation agreement between Brunei and the United Kingdom. Exemption from taxes can be granted by the sultan in council to industries deemed essential for the country's development. By Income Tax Order 2001, companies granted a Pioneer Certificate, foreign or domestic, are exempted from the 30% tax for two to five years, depending on the size of their capital investment, specified in round dollar terms with an obvious eye to outside investors: for less than $250,000 the exemption is for two years; for $250,000 to $500,000, three years; $500,00 to $1 billion, four years; and above $1 billion, five years. Pioneer and export industries are exempt from customs duties on imports of raw materials and capital goods.