After a year suffering the economic consequences of the oil price slump, OPEC is finally on the cusp of choking off growth in U.S. crude output. The nation’s production is almost back down to the level pumped in November, when the Organization of Petroleum Exporting Countries switched its strategy to focus on battering competitors and reclaiming market share. As the U.S. wilts, demand for OPEC’s crude will grow in 2015, ending two years of retreat, the International Energy Agency estimates. While cratering prices and historic cutbacks in drilling have taken their toll on the U.S., OPEC members have also paid a heavy price. A year of plunging government revenues, growing budget deficits and slumping currencies has left several members grappling with severe economic problems . The fact that the U.S. oil boom kept going for about six months after the group’s November decision also means OPEC has so far […]