Parker-Hannifin's return on equity climbed 217 basis points to 18.68%, and cash and cash equivalents rose 6.9% to $187.92 million. However, the company suffers from a declining operating margin as well as a high debt level. In addition, a significant portion of its revenue comes from customers outside the U.S., leaving it susceptible to adverse foreign policy and currency risk. Hewlett-Packard ( HPQ), a technology products and services company, has been rated a buy since September 2005 based on growing revenue, strong cash flow and expanding margins. Third-quarter earnings climbed 29% from a year ago to $1.78 billion, or 66 cents a share. Revenue increased 16% to $25.38 billion. The gain in sales volume was partially offset by a reduction in average selling price, particularly in emerging markets. Ongoing restructuring programs increased operating margins by 140 basis points. The company has made significant progress in improving its competitive position by diversifying its operations, lowering the cost structure and deploying capital in key business segments. Stiff competition and exposure to emerging markets is forcing the company to lower its prices in order to defend its market share. As a result, Hewlett-Packard's margins could deteriorate in the future. Rated a buy since September 2005, Telmex-Telefonos de Mexico ( TFONY) provides fixed-line telephony services in Mexico, the U.S. and numerous countries in Latin America. It has been rated a buy since November 2005 and maintains a largely solid financial position with expanding profit margins, revenue growth and a pattern of EPS growth over the past two years that is likely to continue.