The population counts originate with the census, and are either passed through to census block features or allocated to parcels through the Base Canvas creation process. Group quarters population is allocated to parcels according to land use codes. If group quarters population is indicated for a census block, but there is no way to determine, according to source land use codes, on which parcel(s) they are located, the group quarters population is dispersed over multiple parcels. While likely inaccurate at the parcel level, the location of group quarters population by census block is maintained. Group quarters population is not used as a direct input to the analysis modules, so their specific location has no bearing on analysis results. (Impacts associated with group quarters population are measured via building characteristics -- for example, their energy use is measured according to the building floor area of college dormitories or other facilities. Transportation behavior by group quarters population, who are generally assumed not to drive or drive only minimally, is not measured.)