Even though previous research at South Dakota State Univ. (Dinkel and Brown, 1978) showed that the ratio of a calf’s weaning wt. to its dams wt. as an indicator of cow efficiency had very little advantage over weaning wt. alone in predicting efficiency (TDN consumed by cow and calf divided by calf weaning wt.), there continues to be interest in its use as a measure of efficiency. The objective of the present study at USDA’s Miles City, MT research station was to determine the effectiveness of selecting for calf weight: cow weight ratio over a period of 11 years (2.5 generations). The experiment consisted of two lines, Control and Selected. In brief, the author concluded that the results of the study contraindicate use of the ratio of calf weaning wt. to cow wt. as a selection criterion. He noted that selection index procedures would seemingly yield a more defined criterion, with clear and consistent emphasis on traits and their genetic components (MacNeil, M.D. 2005. J. Anim. Sci. 83: 794).