Professor Philip M'Pherson worked in the Management and Technology Area on sabbatical leave from the Systems Department of the City University, London, UK, from September 1976 to August 1977. He worked on developing models to explore the technological efficiency of socio-economic systems but was unable at the time to obtain sufficient empirical data for adequate testing of his hypotheses. The time series of available data is now long enough for such testing to begin and this paper is the first publication of his results. It was presented at the Fifth European Meeting on Cybernetics and Systems Research and will be published in the proceedings of this meeting by the Hemisphere Publishing Corporation. Fuller and more detailed research reports will follow in the near future.