Since peaking at nearly 318 gigawatts (GW) in 2011, U.S. coal-fired electric generating capacity declined to 257 GW in 2017 after several coal power plants retired. The U.S. Energy Information Administration (EIA) undertook a study with Sargent & Lundy to improve modeling for the Annual Energy Outlook (AEO). The results show the relationship between plant retirements and a plant’s operating and maintenance costs. According to the report, a larger share of plants with higher operating and maintenance costs retired by 2018 than those with relatively low operating and maintenance costs.