<Li> Address: Jalan Sisingamangaraja No. 70A, South Jakarta . </Li> <Li> Calculated using UNDP data from member states . </Li> <P> The Association of Southeast Asian Nations (ASEAN / ˈɑːsi. ɑː n / AH - see - ahn, / ˈɑːzi. ɑː n / AH - zee - ahn) is a regional intergovernmental organisation comprising ten Southeast Asian countries which promotes Pan-Asianism and intergovernmental cooperation and facilitates economic, political, security, military, educational and socio - cultural integration amongst its members and other Asian countries, and globally . Since its formation on 8 August 1967 by Indonesia, Malaysia, the Philippines, Singapore and Thailand, the organisation's membership has expanded to include Brunei, Cambodia, Laos, Myanmar and Vietnam . Its principal aims include accelerating economic growth, social progress, and sociocultural evolution among its members, alongside the protection of regional stability and the provision of a mechanism for member countries to resolve differences peacefully . ASEAN is an official United Nations observer, as well as an active global partner . It also maintains a global network of alliances, and is involved in numerous international affairs . Communication by member states takes place in English . </P> <P> ASEAN covers a land area of 4.4 million square kilometres, 3% of the total land area of Earth . ASEAN territorial waters cover an area about three times larger than its land counterpart, making it particularly important in terms of sea lanes and fisheries . Member countries have a combined population of approximately 640 million people, 8.8% of the world's population, more than EU28, though in terms of land, a bit smaller . In 2015, the organisation's combined nominal GDP had grown to more than USD $2.8 trillion . If ASEAN were a single entity, it would rank as the sixth largest economy in the world, behind the United States, China, Japan, France and Germany . ASEAN shares land borders with India, China, Bangladesh, East Timor and Papua New Guinea, and maritime borders with India, China, Palau and Australia . Both East Timor and Papua New Guinea are backed by certain ASEAN members for their membership in the organisation . </P>

When was asean established and how many members were there at the beginning
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