WASHINGTON (MarketWatch) - New methods in how the government calculates gross domestic product show the U.S. economy actually grew 0.6% in the first quarter instead of contracting by 0.2%. The new approach has been incorporated going back to 2012 to correct for flaws in how the government accounts for some categories such as military outlays and spending on consumer services. Yet U.S. growth from 2012 to 2014 was reduced to an annual average of 2% instead of 2.3% as reported under the old method for calculating GDP. Growth for 2014 was unchanged at 2.4%, but 2013 was chopped to 1.5% from 2.2% and 2013 GDP was trimmed to 2.2% from 2.3%.