Concentration in Indonesia Manufacturing, 1975–93

This paper analyses trends and levels of industrial concentration in 102 Indonesian industries between 1975 and 1993. There was a long-term decline in industrial concentration across the manufacturing sector over this period. The simple average four-firm concentration ratio declined from 64% in 1975 to 54% in 1993, while the percentage of industries classified as highly concentrated fell from 39% in 1975 to 28% in 1993. Allowing for foreign trade substantially reduces average concentration measures: in 1993 the average concentration of a sample of 67 industries was 53% without adjustment for foreign trade, but 41% if foreign trade was allowed for. Thus, competition is stronger in Indonesian markets than domestic concentration ratios would suggest.