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? This title deals with these questions. "GDP is a thought-provoking account of how the gross domestic product statistic came to be so important. . . . The book is a useful and timely contribution."---Louise Rawlings, Economic Record