During the last decade, the Italian national institute of statistics (Istat) has been engaged in a modernization program involving the revision of the statistical production model. The main goal behind this program is the use of statistical registers integrated into a single logical environment, the Italian Integrated System of Statistical Registers (ISSR), for supporting the consistency of statistical production processes and improving the quality of information for users. One object of the ISSR is the satellite statistical REgister for Public Administrations (REPA) that contains information on structural and economic variables on a subset of the Italian PA. The public institutions are different from each other in structures, dimensions, and scopes. In the present paper, these differences are analysed by looking at their revenues. For this aim, the inequality in the revenues, measured with the Gini index, is decomposed “by sources”.