Abstract: This paper uses the system theory to make an abstract definition of the economic results as the efficiency produced by the joint actions of the structural and qualitative elements of productive factors, and deduces its expression as the output that can be supplied by the unit input productive factors which is reduced from the total output excluding the role of quantitative elements of input productive factors; its index form are relative numbers or means of intensity. Finally, the paper makes an analysis of the input meanings in the index components.