The United States has regained its place as the world's number one investor in clean energy, reclaiming the top spot from China, according to Bloomberg New Energy Finance. In 2011, U.S. total investment in clean energy surged to $55.9 billion, up 33 percent from 2010; China saw investment rise just 1 percent to $47.4 billion over the same time period. This is the first time that the U.S. - and not China - has held the number one spot since 2008. Bloomberg attributes the increase in U.S.investment in large part to support initiatives such as the federal loan guarantee program and a Treasury grant program which have now expired. The country's principal remaining support measure for renewable energy, the Production Tax Credit, is currently also scheduled to fall away at the end of 2012 unless it is extended. As a result, Bloomberg suggests that there may be a rush to get projects completed in 2012, followed by a slump in investment in 2013, if the credit does, in fact, expire. Vestas, the world's largest maker of wind turbines in terms of revenue, warned that 1,600 U.S. jobs were at risk if clean energy tax credits were not extended past the end of this year.