NEW YORK (Standard&Poor's CreditWire) May 7, 1999--Standard&Poor's today revised its outlook for PetsMart Inc. to positive from stable. Standard&Poor's also affirmed its single-'B'-plus corporate credit and bank loan ratings, and single-'B'-minus subordinated debt rating for the company. The revised outlook reflects operating improvements in the company's inventory management, positive free operating cash flow in 1998, and efforts to focus operations in its core North American business segment. The ratings reflect PetsMart's operating challenges associated with its aggressive store expansion strategy and thin cash flow protection, mitigated by the company's position as the largest operator of superstores within the stable but competitive pet food, supplies, and services market. Phoenix, Ariz.-based PetsMart is the largest operator