The following parameters have been used to estimate the reliability of predicted first-year corrosion losses of carbon steel and zinc ( $$K_{1}^{{{\text{pr}}}}$$ ): the standard determination coefficient $$R_{{{\text{st}}}}^{2}$$ according to ASTM G 16; statistical indicators such as SMAPE and MAPE; generalized determination coefficients; confidence angle. The experimental data on corrosion losses of carbon steel and zinc ( $$K_{1}^{{{\text{exp}}}}$$ ) and the atmosphere corrosivity parameters were taken from the UN/ECE international program and Russian program. The $$K_{1}^{{{\text{pr}}}}$$ values were calculated using various dose-response functions. It is not recommended to use the standard determination coefficient $$R_{{{\text{st}}}}^{2}$$ in the y = $$K_{1}^{{{\text{pr}}}},$$ x = $$K_{1}^{{{\text{exp}}}}$$ coordinates.