AFP/Getty Images Flags of member states of the Organization of the Petroleum Exporting Countries (OPEC)Oil prices have rallied so far this year, as OPEC-led efforts have helped erase a big global surplus, but the market may soon suffer from a new dilemma: a shortage of crude supplies that would support further price gains. Stockpiles of the commodity among the industrialized nations that make up the Organization for Economic Cooperation and Development (OECD) stood at 2.84 billion barrels at the end of February, only 30 million barrels above the five-year average, according to a monthly report from the International Energy Agency (IEA). “The global market has tightened considerably in recent months,” says Matthew Parry, head of long-term research at research consultancy Energy Aspects. The Organization of the Petroleum Exporting Countries is “very close to achieving its originally stated aim of bringing OECD stocks back to parity with their five-year average.”via