Millions of barrels of untapped oil that U.S. shale drillers discovered during the boom years are about to disappear from their inventories. Six years ago, the industry pushed the Securities and Exchange Commission to make it easier for companies to claim proved reserves for wells that wouldn’t be drilled for years. Some prospects considered sure-things when crude was $95 a barrel are money losers at today’s $60. When crude crashed in 2008, 44 U.S. companies wiped 630 million barrels from their books. Now the stakes are higher. Of all the proved reserves of oil and natural gas liquids found by the 44 companies since 2008, more than half — 5.4 billion barrels out of the 9.7 billion — is attributed to wells that don’t exist yet, according to data compiled by Bloomberg. “We’re going to see a lot of proved undeveloped reserves get vaporized,” said Ed Hirs, a managing […]