The United States in 2011 was a net exporter of petroleum products, prompting one analyst to say the U.S. market is nearly energy independent. Edward Morse, a commodities analyst at Citigroup, told USA Today that the United States imported 49 percent of its oil in 2010, down from 60 percent in 2005. \"It\'s dramatic. It\'s transformative,\" he said. \"We\'re moving toward energy independence.\" The shift, however, means the United States is second, only to China, in terms of greenhouse gas emissions. Some of the lucrative deposits in the United States, notably shale oil and natural gas, are stoking environmental concerns because of chemicals used during extraction. Meanwhile, U.S. refineries are processing a growing amount of so-called tar sands oil from Alberta, Canada, though that too comes with significant environmental risk. In terms of foreign affairs, however, the United States in 2011 imported 12 percent of its oil from Saudi Arabia, down from 19 percent in 1993. High energy prices are prevalent, the newspaper notes, because of world market activity. \"The U.S. has been using less and producing more,\" James Hamilton, an economist at the University of California-San Diego, was quoted as saying.