TheStreet.com Ratings: Stock Upgrades, Downgrades

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

While our 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.

Amsurg(AMSG Quote) has been upgraded to a buy from a hold. The company owns and operates specialty surgery centers throughout the U.S. Amsurg's earnings per share grew 17.9% in the fourth quarter of fiscal 2006 compared with the same quarter a year ago. TheStreet.com Ratings also feels the company's gross profit margins are strong. Amsurg had been rated a hold since November 2006.

Diebold(DBD Quote) has been upgraded to a buy from a hold. The company sells self-service banking and security systems as well as voting machines. Net income went up 160.3% in the fourth quarter of fiscal 2006 compared with the same quarter a year earlier. Diebold has demonstrated a pattern of positive earnings per share growth over the past 12 months. TheStreet.com Ratings feels this trend will continue. Diebold had been rated a hold since October 2005.