Malaysia is a Southeast Asian republic. The federal constitutional monarchy is made up of thirteen states and three federal territories that are divided into Peninsular Malaysia and Borneo's East Malaysia by the South China Sea. Peninsular Malaysia borders Thailand on land and sea, as well as Singapore, Vietnam, and Indonesia on the sea. East Malaysia is bordered on the land and sea by Brunei and Indonesia, as well as a maritime boundary with the Philippines and Vietnam. The national capital and largest city is Kuala Lumpur, while the federal government's seat is Putrajaya. Malaysia is the world's 43rd most populous nation, with a population of over 32 million people. Tanjung Piai is the southernmost point of continental Eurasia. Malaysia is one of 17 megadiverse countries in the tropics, home to a host of endangered species. Malaysia has its roots in the Malay kingdoms, which were part of the British Empire in the 18th century, along with the protectorate of the British Straits Settlements. In 1946, Peninsular Malaysia was united as the Malayan Union. In 1948, Malaya was restructured as the Federation of Malaya, and on August 31, 1957, it gained independence. On September 16, 1963, Malaya, North Borneo, Sarawak, and Singapore merged to form Malaysia. Singapore was expelled from the union in 1965. The country is multi-ethnic and multi-cultural, which has an effect on politics. The Malay ethnic group makes up about half of the population, with minorities of Chinese, Indians, and indigenous peoples. Malaysian, a standard version of Malay, is the country's official language. English is still used as a second language. While the constitution recognizes Islam as the country's official religion, it also grants non-Muslims religious freedom. The legal system is based on common law and the government is modeled after the Westminster parliamentary system. Every five years, an elected monarch is chosen from among the nine state sultans to serve as the country's head of state. The Prime Minister is in charge of the government. Malaysia's GDP rose at an annual rate of 6.5% for nearly 50 years after independence. The economy has historically been fueled by natural resources, but science, tourism, trade, and medical tourism are all growing. Malaysia has a newly industrialized market economy, which is the third-largest in Southeast Asia and the world's 33rd-largest. It is a founding member of ASEAN, EAS, and the Organization of Islamic Cooperation, as well as APEC, the Commonwealth, and the Non-Aligned Movement.