ABSTRACT
A particular national economy can and, in the context or the planning process, has to be visualized as a system consisting of mutually interdependent parts. The trucking industry must be supplied with fuel by the oil refining sector; in order to expand, it must be supplied by the automobile industry with vehicles as well as replacements for worn-out equipment. Conventional monetary and fiscal policies relying on a rather sketchy aggregative description and analysis of the economic system appear to be no more successful in compensating for the lack of systematic foresight than frantic pushing and pulling of the choke is able to correct the malfunctioning of a motor. The data base, the computing facilities, and the analytical techniques have advanced much farther than could have been anticipated forty years ago. National input-output tables containing up to TOO distinct sectors are being compiled on a current basis, as are tables for individual, regional, state, and metropolitan areas.
