Editor's Note: TheStreet ratings do not represent the views of TheStreet's staff or its contributors. Ratings are established by computer based on metrics for performance (which includes growth, stock performance, efficiency and valuation) and risk ( volatility and solvency). Companies with poor cash flow or high debt levels tend to earn lower ratings in our model. NEW YORK ( TheStreet ) -- Align Technology (Nasdaq: ALGN ) has been downgraded by TheStreet Ratings from buy to hold. The company's strengths can be seen in multiple areas, such as its revenue growth, largely solid financial position with reasonable debt levels by most measures and increase in stock price during the past year. However, as a counter to these strengths, we also find weaknesses including deteriorating net income, disappointing return on equity and feeble growth in the company's earnings per share. Highlights from the ratings report include:.