TheStreet.com Ratings: Stock Upgrades, Downgrades

Each weekday, TheStreet.com Ratings updates its ratings on the stocks it covers. The proprietary ratings model projects a stock's total return potential over a 12-month period including both price appreciation and dividends. Buy, hold or sell ratings designate how the Ratings group expects these stocks to perform against a general benchmark of the equities market and interest rates.

While the ratings model is quantitative, it uses both subjective and objective elements. For instance, subjective elements include expected equities market returns, future interest rates, implied industry outlook and forecasted company earnings. Objective elements include volatility of past operating revenue, financial strength and company cash flows.

Some recent rating changes are highlighted below.

Semiconductor manufacturer Advanced Micro Devices(AMD Quote) has been downgraded to a sell from a hold. The company lost $1.08 in the fourth quarter of fiscal 2006 after gaining 21 cents the same quarter a year earlier. Return on equity has also declined, which TheStreet.com Ratings feels is a sign of significant weakness within AMD. Advanced Micro Devices had been rated a hold since August 2006.

Russian telephone company Rostelekom(ROS Quote) has been upgraded to a buy from a hold. The company's revenue grew 58.5% in the third quarter of fiscal 2006 compared with the same quarter a year ago. TheStreet.com Ratings feels Rostelekom has been successful at managing its debt and is well-prepared to cover short-term liquidity needs. With the market expecting an improvement in earnings per share going forward, the company's stock price should continue to move higher. Rostelekom had been rated a hold since March 2007.