Constellation Energy is a fortune 200 company and is recognized as the leading competitive electricity reseller in the US. The parent company, Exelon, operates in 47 states and Washington DC. Has revenues of $32.7 billion (2011) with assets of $74.5 billion (2011). It is one of the largest competitive power generators in the nation with a generating capacity of 34,650 MW (2011). The company provides service to 6.6 million electric customers and 1.2 million natural gas customers. The NYSE ticker symbol is EXC.