The operational efficiency of a retailer is defined by its supply-chain management (SCM) mechanisms. When determining the efficiency of a retailer’s supply-chain management, the most commonly utilized metric is inventory turnover (IT). This econometric study systematically examines the relationship between SCM efficiency and IT rates by extracting inventory-based data for four global apparel retailers- Zara, Uniqlo, H&M, and Gap. The theoretical purpose of this study is to link quantitative analytics of top-grossing apparel retailers to operational conclusions.