THE FOLLOWING GRAPHS are based on Official Proceedings, 1896–1956; various issues of International Musician and Overture; Everett Lee Refior, “The American Federation of Musicians: Organization, Policies, and Practices” (master’s thesis, University of Chicago, 1955), 55; and Robert D. Leiter, The Musicians and Petrillo (New York: Bookman Associates, 1953), 80.
Total membership figures for 1901–3, 1911–12, 1914, and 1919–28 are contradictory or not available. For the years 1901–3, 1911–12, and 1914, membership figures in the graph are linearly interpolated from nearby known data. For 1919–28, figures were obtained by linear extrapolation from membership of ten representative locals.
Number of Locals in the AFM, 1896–1956