The weighting for the group quarters population is controlled at the state level. For that reason, users should expect that the ACS estimate for the group quarters population to be consistent with the Population Estimates Program only at the state level. For sub-state areas, the ACS estimate will typically be different from the Population Estimates Program due to sampling variability. Like estimates of total population, data users who require an estimate of the group quarters population at the county level should use the official estimates from the Population Estimates Program.