Data for the surface of magnetization, temperature, and field for single crystal nickel are compared with the parametric equation of state of Schofield, Litster, and Ho [Phys. Rev. Lett.23, 1098 (1969)]. An excellent fit to the magnetic isotherms is obtained by choosing a reduced temperature for each isotherm, and the variation of the reduced temperature with measured temperature is linear above and below the critical temperature. But whereas the five parameter equation would demand that the slope be the same above and belowTc, the experiments show a 15% change in slope. It is argued that a six parameter equation is needed for the experimental fit and a suitable equation is given.