The bear market in oil has analysts reassessing the U.S. shale boom after five years of historic growth. The U.S. benchmark price dropped to $79.78 a barrel on Oct. 16, the lowest since June 2012. At that level, one-third of U.S. shale oil production would be uneconomic, analysts for New York-based Sanford C. Bernstein & Co. led by Bob Brackett said in a report yesterday. Drillers would add fewer barrels to domestic output than the previous year for the first time since 2010, according to Macquarie Group Ltd., ITG Investment Research and PKVerleger LLC. Horizontal drilling through shale accounts for as much as 55 ... (full story)