Prices on shares in selected power companies and in companies with largetrading activity in electricity:December 20COMPANY Latest close Change % VolumeSTOCKHOLM (SEK)Arise Windpower 42,60 -0,23 51 732Eolus Vind 42,40 -0,24 43 733Holmen 211,50 0,05 200Stora Enso 65,50 0,85 10 375COPENHAGEN (DKK)Vestas Wind Systems 174,10 -4,66 1 913 782HELSINKI (EUR)Fortum 22,08 2,36 1 450 043Stora Enso 7,27 0,83 7 484OSLO (NOK)Arendals...