OPEC is welcoming a new member. Indonesia is rejoining the powerful oil cartel after a seven-year break. The country is looking to boost investment and increase production as it faces growing demand for oil. The 12 -- soon to be 13 -- OPEC nations have played a key role in the oil market turmoil. The Saudi-led group refused to cut production even as prices collapsed. It is instead determined to defend its market share by squeezing out producers who cannot cope with the low prices. The strategy has been paying off. Many oil producing countries, such as Russia, Venezuela, and Canada, have been hit by the low prices. Shale oil producers in the U.S. are struggling. Indonesia will be among OPEC members with the lowest oil production. According to a forecast by the International Energy Agency, the country is set to produce on average 870,000 barrels per day in 2015. That is roughly a half of Indonesia's output during the peak in the late 1970s. It suspended its membership in 2009, after a slide in its output. http://money.cnn.com/2015/09/08/news/economy/indonesia-opec-...