The following ratings changes were generated on Monday, Dec. 22. We've upgraded AthenaHealth ( ATHN), which provides Internet-based business services for physician practices, from sell to hold. Strengths include its robust revenue growth, largely solid financial position with reasonable debt levels by most measures and notable return on equity. However, we also find weaknesses including premium valuation and a decline in the stock price during the past year. Revenue rose by 35.4% since the same quarter a year ago, outperforming the industry average of 3.7% growth and boosting earnings per share. AthenaHealth's debt-to-equity ratio is very low at 0.1 and is currently below that of the industry average, implying very successful management of debt levels. The company also maintains a quick ratio of 4, which clearly demonstrates its ability to cover short-term cash needs. Shares are down 14.6% on the year, in part reflecting the market's overall decline, but the stock is still selling for more than most others in its industry. We don't see anything in the company's numbers that may help reverse the decline experienced over the past 12 months. We've downgraded Copel-CIA ( ELP), which generates, transmits and distributes electricity in Brazil, from buy to hold. Strengths include its largely solid financial position with reasonable debt levels by most measures, notable return on equity and attractive valuation levels. However, we also find weaknesses including unimpressive growth in net income, weak operating cash flow and poor profit margins. Copel's debt-to-equity ratio is very low at 0.2 and is currently below that of the industry average, implying very successful management of debt levels. The company's 1.6 quick ratio demonstrates its ability of the company to cover short-term liquidity needs. Return on equity has improved slightly, which can be construed as a modest strength in the organization. On the basis of ROE, Copel outperforms the industry and the S&P 500.