Each business day, 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. ConAgra Foods ( CAG), a packaged food company, has been upgraded to buy. The company has experienced an increase in net income, attractive valuation levels, good cash flow from operations and growth in revenue and earnings per share. These strengths should outweigh the stock's lackluster performance. Fiscal second-quarter earnings totaled $244.8 million, or 50 cents a share, compared with $213.3 million, or 42 cents a share, a year ago. Income growth has exceeded the food products industry average. ConAgra has demonstrated a pattern of positive EPS growth over the past two years and this trend is expected to continue. Revenue increased 13.7% to $3.51 billion. The company also raised its profit outlook for the full year. ConAgra Foods had been rated hold since March.