ECSENOMICS Concentration Ratios Are Quantitative Measures of market Power 1-75 Figure 10-1 Concentration Measured by Value of Shipments in Manufacturing Industries, 1992 4 largest companies Next 4 largest companies Cigarettes 93% Household refrigerators Electric lightbulbs 86%6 Motor vehicl Screw products Tools, dies, and jigs Percent of total shipments McGraw-Hilllrwin CopyrightC 2001 The McGraw-Hill Companies, Inc. All rights reserved.McGraw-Hill/Irwin Copyright © 2001 The McGraw-Hill Companies, Inc. All rights reserved. Concentration Ratios Are Quantitative Measures of Market Power T-75 Figure 10-1