This study presents a scheme for yearly, comparative, computation of state and local government tax capacity and effort. Figures for all states for fiscal year 1975 are presented in extensive tables. The system used is a simplified version of the Representative Tax System, which identifies tax bases, determines national average tax rates for those bases, and uses these figures to determine each state's reasonable taxing capacity. The system also provides for comparing actual taxing performance against these capacities to reveal relative tax effort. The methodology for using these measures is investigated in the remainder of the document. Appendices on fiscal capacity and revenue requirements, problems in tax capacity measurement, and personal income as a gauge of fiscal capacity are also included. (Author/PGD)