Growth curves of 255 pigs weighed at 10 day intervals between 134 and 174 days of age were essentially linear over this period. Growth curves varied for particular pigs, each being a linear function of the weight attained at a given age. A common intercept of -45 days on the age axis and -154 lb. on the weight axis fitted data for both fast and slow-growing pigs, assuming linearity of growth over the period from 134 to 174 days. Several methods of adjusting weights to a standard age of 154 days were examined. One of the most accurate and convenient was: Adjusted weight = Actual weight + 154) (199) -Actual age + 45 Linear interpolation was also an accurate and convenient method when 2 weights of each animal are available.