Performance effectiveness of Russian energy companies based on EVA and DEA Irina Filimonova, Vasiliy Nemov, Irina Provornaya, Anastasia Chebotareva and Victor Butenko E3S Web Conf., 330 (2021) 01007 Published online: 09 December 2021 DOI: 10.1051/e3sconf/202133001007