Changes in Concentration in Manufacturing Industries in the United States, 1954-1966: Trends and Relationships to the Levels of 1954 Concentration

Abstract

PpT HIS presentation of descriptive statistics is designed to explore two main questions concerning changes in seller concentration in American manufacturing industries from 1954 to 1966: 1) Over this period, was there any significant upward or downward trend in individual-industry concentration ratios, as indicated both by the frequencies of positive and negative concentration changes, and by the size distributions of these changes? (And, as a sub-question, were there any significant shifts between 1963 and 1966?) 2) WVas there, over the period in question, any systematic relationship between the directions and sizes of concentration changes in individual industries and their concentration ratios in 1954? ' We pose the first question because we would like to know to what extent individual-industry concentration has been responsive since 1954 to increases in the shares of all manufacturing activity controlled by the largest 50, 100, and 200 manufacturing firms, and to the considerable number of large manufacturing mergers. Statistics prepared by the Bureau of Census show a large increase from 1947 to 1954 in the share of total value added by manufacture accounted for by the largest manufacturing firms, and a smaller increase from 1958 to 1963, as follows: 2 Share of total value added by manufacture accounted for by: