The ratings on CVS Corp. reflect the company's leading position in the favorably regarded drug store industry and the belief that management is committed to maintaining a moderate financial policy. CVS, with more than 4,100 units, is the nation's top chain drug retailer based on store count. Prescriptions, which comprise about 66% of the company's revenue, continue to drive growth and are expected to do so well into the future based on an aging population, greater use of pharmaceuticals in outpatient therapy, and the ongoing development of new drug products. The company has historically generated consistent operating performance but has had difficulty since the third quarter of 2001 due to a shortage of pharmacists in four of its major markets,