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. However, the rating does not incorporate all of the factors that can alter a stock's performance. For example, it doesn't always factor in recent corporate or industry events that could affect the stock price, nor does it include recent technology developments and competitive dynamics that may affect the company. For those reasons, we believe a rating alone cannot tell the whole story, and that it should be part of an investor's overall research. The following ratings changes were generated on August 27. Watts Water Technologies ( WTS) was upgraded from hold to buy. Watts Water Technologies, through its subsidiaries, designs, manufactures and sells water safety and flow control products primarily for the water quality, water safety, water flow control and water conservation markets in North America, Europe and China. The company's strengths can be seen in multiple areas, such as its increase in net income, revenue growth, largely solid financial position with reasonable debt levels by most measures, good cash flow from operations and expanding profit margins. We feel these strengths outweigh the fact that the company has had somewhat disappointing return on equity.