The American Customer Satisfaction Index (ACSI) stands as the sole national benchmark measuring customer satisfaction across U.S. industries, evaluating both domestic and foreign firms with substantial market presence. For over twenty years, ACSI has employed a scientifically grounded, proprietary methodology developed at the University of Michigan's Ross School of Business to assess satisfaction through consumer interviews and an econometric cause-and-effect model. Covering 40 industries across 10 economic sectors, ACSI generates weighted benchmarks that reflect both company and sector performance. This comprehensive approach benefits businesses, researchers, policymakers, and consumers by offering insights into firm competitiveness, forecasting profitability, and acting as a vital indicator of the health of the U.S. economy.