8,243 performance tested bulls were analysed using random regression (RR) and single trait animal models. Evaluations were for line weight at age 400 days and gains in monthly intervals. RR covers fixed effect of test day of weighing, average fixed curves for groups of animals and random curves of animal´s additive genetic and permanent environment. Variance components, correlations between methods, parents-offspring correlations within methods and cross the independent data sets were calculated. The evaluation of growth of animals according to daily gains in short consecutive interval was preferred.