Jonathan: The World Health Organization and UNICEF are in the process of developing a project to collect data on healthy breastfed infants/toddlers world-wide. These data will then be used to develop a new growth chart for children, which hopefully will be available within the next few years. Apparently, there are efforts also in the USA to develop a only-USA based data set, as well as one in Europe. For now, one can get an idea of what breastfed babies growth curve looks like through small studies, such as those carried out by K. Dewey, from the U. of CA at Davis. See: Dewey KG, Heinig MJ, et al. Growth of breast-fed and formula-fed infants from 0 to 18 months: The DARLING study. Pediatrics Vol 89, No. 6, pp. 1035-1041. 1992.