The Central American Common Market (CACM) was established in 1960 with the signing of the General Treaty of Central American Integration at Managua, Nicaragua. The original signatories of the treaty, which became effective June 3, 1961, were El Salvador, Guatemala, Honduras, and Nicaragua. Costa Rica joined the market in 1962. Panama has observer status in the market and along with Belize participates in the CACM summits, but neither are involved in regional trade integration activities. Including Panama the CACM encompasses a market of 31 million people with a combined gross domestic product (GDP) of over $92.8 billion, for an average per capita GDP of approximately $2,984
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