In 2010, America’s proved oil reserves stood at 31 billion barrels, just slightly below the 33.8 billion barrels of proved reserves the United States had in 1990. But over that two-decade period, the domestic oil sector produced about 52 billion barrels of oil. In other words, between 1990 and 2010, the United States produced nearly twice as much oil as we believed the whole country had in 1990, and yet at the end of that period, we still had about the same amount in proven reserves. What’s going on? In a word: innovation. And few industries on the planet have been as innovative as the American oil and gas sector.