The Department of Transportation and U.S. EPA have issued a final joint rulemaking setting the nation's first greenhouse gas emission standards, and new stringent fuel-economy standards, for 2012 through 2016 model-year vehicles. "They require these vehicles to meet an estimated combined average emissions level of 250 grams of carbon dioxide per mile, equivalent to 35.5 miles per gallon (MPG) if the automobile industry were to meet this carbon dioxide level solely through fuel economy improvements. Together, these standards will cut greenhouse gas emissions by an estimated 960 million metric tons and 1.8 billion barrels of oil over the lifetime of the vehicles sold under the program (model years 2012-2016)."
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