A year ago, the Organization of the Petroleum Exporting Countries (OPEC) decided not to reduce supply to maintain market share against competitors with higher costs. However, in its 2015 World Oil Outlook, OPEC increased its global supply predictions for tight oil, including shale, despite the significant drop in prices. OPEC stated that demand for their crude oil will be 30.70 million barrels per day (bpd) in 2020, slightly lower than the anticipated 30.90 million bpd for the following year. The organization is currently producing about 1 million bpd more than what is expected to be demanded in 2020. Oil prices have decreased by more than half in the last 18 months, reaching an 11-year low of $36.04 per barrel this week. While the drop in prices has led to increased use of oil in the short term, OPEC believes that the demand boost from low prices will diminish over time. OPEC Secretary-General Abdullah al-Badri stated in the report that the recent decline in oil prices has had a significant impact on demand, particularly in the short term, with the effects diminishing over the medium term. Despite disagreements within OPEC over the market-share strategy implemented in 2014, the report indicates an improved medium-term outlook for OPEC as a major oil supplier. The 2014 edition of the report had projected a decrease in demand for OPEC crude to 29.0 million bpd by 2020. OPEC has ceased working on the report midway through the year and has since updated its forecast for a decline in 2016 non-OPEC supply. The report does not include Indonesia, which rejoined in December. The main figures regarding OPEC's medium-term market share pressure remain the same as a confidential report obtained by Reuters in November. OPEC initially underestimated the impact of shale oil, but later recognized its significance in its annual outlook in 2012. The years of high prices, supported by OPEC's previous supply-cutting policy, contributed to the viability of non-conventional oil like shale. OPEC's recent report indicates a shift in perspective, noting that many projects can remain profitable at lower prices. Some of the most productive areas in certain plays can break even at prices lower than those seen in 2015, suggesting that production growth will continue. The report predicts that global tight oil output will increase to 5.19 million bpd by 2020, peak at 5.61 million bpd in 2030, and then decrease to 5.18 million bpd in 2040. Argentina and Russia are expected to become major producers alongside North America. Previous estimates projected 4.50 million bpd by 2020 and 4 million bpd by 2040. In a more optimistic scenario, tight oil production could expand to Mexico and China, potentially reaching almost 8 million bpd by 2040 according to OPEC. In 2013, OPEC believed that tight oil would only have an impact in North America. However, a recent report suggests that OPEC's market share will increase over time as competitor supply growth diminishes. OPEC predicts that their crude demand will reach 40.70 million bpd by 2040, making up 37 percent of global supply compared to 33 percent in 2015. OPEC has slightly raised its forecast for world oil demand in the medium-term, expecting it to reach 97.40 million bpd by 2020, which is 500,000 bpd more than previously estimated. Nevertheless, factors such as slower economic growth, the small portion of crude oil costs in pump prices, and the depreciation of some currencies against the dollar will restrict the response to lower crude oil prices, according to OPEC. OPEC predicts that by 2040, demand will reach 109.80 million bpd, which is 1.3 million bpd lower than the previous year due to increased energy efficiency and climate change initiatives. The report anticipates only a modest increase in oil prices, with OPEC's basket of crude oils starting at $55 in 2015 and rising by $5 annually to reach $80 by 2020.