Getty Images Workers with Raven Drilling line up pipe while drilling for oil in the Bakken shale formationAfter two years of significant declines in upstream oil investments, the sector is finally facing a rebound in 2017 and it all comes down to one thing: A sharp jump in money flowing into U.S. shale oil projects. In a report out on Tuesday, the International Energy Agency predicts a 53% upswing in shale investments this year, even as oil prices are struggling to make a sustainable push above $50 a barrel. “The largest planned increase in upstream spending in 2017 in percentage terms is in the United States, in particular in shale assets that have benefited from a reduction in breakeven prices as a result of a combination of improvement in costs and efficiency gains,” the IEA said.via