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The growth rate in real gross domestic product (GDP) is a conventional indicator of the economy’s health. But the two ways of measuring annual GDP growth can give very different answers. In 2013, GDP grew 2.2 percent on a year-over-year basis, but at a faster 3.1 percent rate on a Q4-over-Q4 basis. So, which measure is more meaningful? We show in this post that the Q4/Q4 metric is better since it only considers quarterly growth rates during the current year, while the Year/Year measure depends on quarterly growth rates in both the current and previous year and puts considerable weight on growth around the turn of the year.