Fig. 4. Change over time in estimated population size and floodplain charcoal from village settlements in the Mimbres region. Population estimates for the Mimbres case are based on a large settlement database compiled as part of the Long Term Vulnerability and Transformation Project. The settlement database includes all sites in major full-coverage surveys across the region, as well as all known large sites (i.e., sites with approximately 30 rooms or more). The population estimates were produced by placing sites in each time period into a number of site size classes based on the best known and recorded components in the database for a particular time period. Sites for which less information was available were placed in size classes based on the available data and were assigned the mean room count of sites in that size class. Following Nelson and Schollmeyer (2003), each 2.5 rooms was assumed to represent one nuclear family household of approximately four individuals. Room-use life estimates were assumed to be roughly 50 years for the purposes of this analysis. The database is likely missing a large proportion of sites dating to the earliest time periods (Early and Late Pithouse periods: AD 400–1000). Thus, population estimates for the earliest periods were defined based on the rates of growth in the best-known portions of the region (Blake et al. 1986).