Abstract
This paper describes the number on books and periodicals according to academic fields per year in Japan and the world, as a basic data for the planning of academic libraries. The sources of the investigated data are Japan Books and Periodicals Directory, Japan Reference Books Directory, UNESCO Statistical Yearbook, Ulrich's International Periodicals Directory, and so on. Contents : 1) Number of titles on books and periodicals issued per year in Japan by N.D.C. classes. 2) Number of titles on books and periodicals issued per year in the world by D.D.C. or U.D.C. classes. 3) Tendency of increase of the issues in Japan. 4) Tendency of increase of the issues in the world.