Each business day, TheStreet.com Ratings updates its ratings on the stocks it covers. The proprietary ratings model projects a stocks total return potential over a 12-month period, including both prices 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 July 16. Telecommunications Systems ( TSYS), a wireless data communications company, has been upgraded to hold. Revenue growth beat the industry average, with revenue increasing 21% from the same quarter last year. Net income also increased significantly from the same quarter last year, shooting up 152%. One concern is a slightly high debt-to-equity ratio of 0.37, indicating that further evaluation of debt level management is needed. Share value has declined over the past 12 months by 2%, meaning there is not enough justification for anything more than a hold rating at this point. Telecommunications Systems had been rated sell since ratings were initiated on July 14, 2006.