The ratings on AutoZone Inc. reflect the company's leading position in the stable but highly competitive retail automobile parts aftermarket, consistent operating performance, and strong profitability measures. These strengths are tempered by increased leverage over the past few years resulting from increased share repurchase activity. Memphis, Tenn.-based AutoZone is the largest retailer of automotive parts in the U.S., with more than 3,000 stores in 42 states and Mexico. Although consolidation in the industry has resulted in five players maintaining significant market shares, AutoZone remains the largest and most geographically diverse in the U.S. This allows the company to take advantage of economies of scale in purchasing and advertising. The company's core do-it-yourself (DIY) market has grown about 5% annually and