This examination of numeric data base activities grew out of a continuing effort to develop a system of statistical indicators of scientific and technical communication. A broad mix of directories, listing by subject field, reports, mail inquiries and telephone and face-to-face interviews was used to collect information. Scientific and technical numeric data bases are identified and described in the following fields: physical, environmental, life and social sciences. Principal federal agencies supporting these data base activities include the National Oceanographic and Atmospheric Administration, Environmental Protection Agency, National Cancer Institute, Energy Research and Development Administration, National Space Science Data Center, United States Geological Survey, National Standard Reference Data System, National Archives and Records Service, U.S. Naval Observatory, Federal Energy Administration, and activities associated with Information Analysis Centers and federal statistical programs. This report provides information individually about some numeric data bases and collectively about some groups of data bases. There is some information about non-numeric aspects of data bases which also contain numeric data. The information collected about numeric data bases differs markedly from data base to data base. For some data bases, numbers of items in the file can be quoted and perhaps even growth rates. For some data bases, information is available concerning dollar costs, number of users, or number of queries. (Author/BB)