Qualified statistical data belong to the instruments of effective association work. Therefore the association, among other activities, carries out statistical investigations on business management among its member enterprises at intervals of two years. This volume contains the results of the business years 1976 and 1977. A main purpose of this statistics is to offer guidelines to the member enterprises, especially figures which allow to compare the evaluated average values of the business with data of the own enterprise, which may be, if necessary, an impetus to think about measures of rationalization. As in former statistics all the results are classified in seven categories that are determined by the size of the enterprise. Compared with the last questionnaire some items have been altered to facilitate the completion. Questions concerning the extent of the public utilities, the structure of the network system and investment planning have been introduced for the first time.