The ratings on Memphis, Tenn.-based 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 somewhat tempered by management's historically aggressive share repurchase activity and soft same-store sales in recent years. AutoZone is the largest retailer of automotive parts in the U.S., with more than 3,655 stores in 49 states and 88 stores in Mexico. Consolidation in the industry has resulted in the top five players having around a 30% market share. AutoZone's large size and geographic diversity have enabled it to take advantage of economies of scale in purchasing and advertising. The company's core do-it-yourself (DIY) market has grown about 4.3% annually
