Stock Upgrades, Downgrades From TheStreet.com Ratings

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 company earnings forecasts. Objective elements include volatility of past operating revenue, financial strength and company cash flows.

Movie rental retailer Blockbuster(BBI Quote) has been downgraded to sell from hold. The company lost 27 cents per share in the first quarter of fiscal 2007 after earnings 4 cents per share a year earlier. Net operating cash flow has decreased significantly during that same time period. In light of these weaknesses, the stock has fallen 44.6% in just the past three months. Blockbuster had been rated a hold since March 2007.

Real estate investment trust Duke Realty(DRE Quote) has been downgraded to hold from buy. The company's 29% gross profit margin is lower than what is desirable. The company's stock has risen in value by 8.6% in the past year, bringing it to a point where it is in line with the industry average in terms of its price-to-earnings ratio. TheStreet.com Ratings feels this tends to reduce its upside potential. Duke Realty had been rated a buy since August 2006.