U.S. energy-related carbon dioxide emissions (CO2) have declined in five of the past eight years. This trend has been led by emissions reductions in the electric power sector. Electricity demand growth has been lower than in the past and at the same time the power sector has become less carbon intensive (measured as CO2 emitted per kilowatthour of generation). Total emissions from the electric power sector in 2013 totaled 2,053 million metric tons (MMmt), about 15% below their 2005 level.