It is suggested that the Tchebycheff criterion for obtaining a best fit of empirical expressions to gamma-ray buildup factor data may be preferable to the least-squares method which has often been used. On this basis, parameters for the Berger formula used in connection with point-source buildup factor data have been calculated for comparison with similar data previously determined on the least-squares basis. Maximum percentage errors when Tchebycheff parameters are used turn out to be equal to or smaller than the corresponding maximum errors using least-squares parameters.