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. Herman Miller ( MLHR) designs and distributes interior furnishings for a variety of settings. It has been upgraded to a buy from a hold. The company's strengths include its revenue growth, notable return on equity and good cash flow from operations. Herman Miller's earnings rose 19.6% to 67 cents per share in the second quarter of its fiscal 2008 compared with 56 cents a share in the same period last year. The company's stock price has fallen by 12.08% in the past 12 months, but given its other strengths, the price level presents an attractive buy opportunity. Herman Miller had been rated a hold since Nov. 13, prior to which it had been rated a buy since December 2005.