Why did the size of the U.S. economy increase by 3 percent on one day in mid-2013--or Ghana´s balloon by 60 percent overnight in 2010? Why did the U.K. financial industry show its fastest expansion ever at the end of 2008--just as the world´s financial system went into meltdown? And why was Greece´s chief statistician charged with treason in 2013 for apparently doing nothing more than trying to accurately report the size of his country´s economy? The answers to all these questions lie in the way we define and measure national economies around the world: Gross Domestic Product. This entertaining and informative book tells the story of GDP, making sense of a statistic that appears constantly in the news, business, and politics, and that seems to rule our lives--but that hardly anyone actually understands.