The article is aimed at studying the methods of economic assessment of regulation results; selection of criterion, as well as improvement of the economic-mathematical instrumentarium for assessing changes after the implementation of regulation measures. As a result of the research, the criterion for assessment of changes after regulation has been suggested, sequence of economic assessment of regulatory managerial decisions on improvement of the production-economic activity of enterprise has been determined, the possibility to track changes in the key indicators and calculate their relative change in order to determine the effectiveness of these decisions by comparing several regulatory decisions has been substantiated. The obtained results on the economic assessment of regulatory decisions allow automating of the process of analyzing measures to improve the performance of enterprise and serve as a component of information support for its leaders. The proposed economic-mathematical instrumentarium can be implemented to analyze the performance of a number of enterprises, which will provide to form a set of proposals to improve their competitiveness in general.