NEW YORK ( TheStreet) -- CHANGE IN RATINGS Accretive Health ( AH) was upgraded from Perform to Outperform at Oppenheimer. $31 price target. Well-positioned to meet or exceed revenue expectations for 2012, Oppenheimer said. AIMCO ( AIV) was upgraded at UBS from Sell to Neutral. $21 price target. Waning demand trends are priced into shares, UBS said. Calpine ( CPN) was downgraded at Jefferies from Buy to Hold. $15 price target. Weakened price forecasts for gas and power, Jefferies said. Electronic Arts ( ERTS) was upgraded at Citigroup from Neutral to Buy. $26 price target. Valuation call, Citigroup said. McDermott ( MDR) was initiated with a Buy rating at Stifel Nicolaus. $16 price target. Company is seeing a solid pricing environment, Stifel Nicolaus said. Navistar ( NAV) was upgraded at Goldman Sachs from Sell to Neutral. Valuation call, based on a $38 price target, Goldman said. Netflix ( NFLX) was downgraded at Wedbush Securities from Neutral to Underperform. $45 price target. Company continues to face higher content costs, Wedbush said. OneBeacon Insurance ( OB) was upgraded to Buy at TheStreet Ratings. Rada Electronics Industries ( RADA) was downgraded to Sell at TheStreet Ratings. Transocean ( RIG) was downgraded at Argus Research from Buy to Hold. Company had a weak November fleet report, and the share raise will dilute earnings, Argus said. Vulcan Materials ( VMC) was downgraded at Goldman Sachs to Sell. $29 price target. Company could face excess capacity in concrete and asphalt mix, Goldman said. $29 price target.