Aetna ( AET) pushed the Health Care sector lower today making it today's featured Health Care loser. The sector as a whole was unchanged today. By the end of trading, Aetna fell $4.05 (-8.2%) to $45.31 on heavy volume. Throughout the day, 17.6 million shares of Aetna exchanged hands as compared to its average daily volume of 3.7 million shares. The stock ranged in price between $43.34-$45.70 after having opened the day at $44.30 as compared to the previous trading day's close of $49.36. Other company's within the Health Care sector that declined today were: Repligen Corporation ( RGEN), down 40.2%, Transcept Pharmaceuticals ( TSPT), down 15.6%, Cytokinetics ( CYTK), down 13.3%, and Graymark Healthcare ( GRMH), down 12.5%. Aetna Inc. operates as a diversified health care benefits company in the United States. The company operates in three segments: Health Care, Group Insurance, and Large Case Pensions. Aetna has a market cap of $17.09 billion and is part of the health services industry. The company has a P/E ratio of 9.4, equal to the average health services industry P/E ratio and below the S&P 500 P/E ratio of 17.7. Shares are up 17% year to date as of the close of trading on Wednesday. Currently there are 11 analysts that rate Aetna a buy, no analysts rate it a sell, and five rate it a hold. TheStreet Ratings rates Aetna as a buy. The company's strengths can be seen in multiple areas, such as its increase in net income, revenue growth, solid stock price performance, attractive valuation levels and largely solid financial position with reasonable debt levels by most measures. We feel these strengths outweigh the fact that the company shows weak operating cash flow.