American Housing Survey. DHUDNational and metropolitan statistics for apartments, single-family homes, mobile homes, vacant homes, family composition, income, housing and neighborhood quality, housing costs, equipment, fuels, size of housing unit, and recent movers. National data are collected every other year, from a fixed sample of about 50,000 homes, plus new construction each year. The survey started in 1973, and has had the same sample since 1985, letting you see homes and households changing over the years.