Abstract: An equation of state (formulation) is an empirical relation to understand the tendency and inter- or extrapolation of experimental thermodynamic data. Two aspects to be considered in creating the empirical formulation are: (a) thermodynamic consistency among the experimental data and (b) retaining the consistency in the formulation for whole range of independent variables. The most recent formulation, IAPWS-95 for the steam tables of pure water was creating by fitting the experimental data in a multi-parameter equation of state. The PVT characteristics of water are consistent with the laws of thermodynamics; however, there are thermodynamic inconsistencies in behavior of U, H, G and S. There are multiple values and crossings in the tendency. The experimental data of heat capacity are used to calculate the values of U, H, G and S. It is found that the experimental values of C_P are inconsistent thermodynamically; consequently, the IAPWS-95 predicts inconsistent values.