Crowded housing has long been used as an indicator of housing affordability and substandard living conditions. The measure used here is the percentage of households living in rental quarters where the number of people living the quarters exceeds the total number of rooms.
A number of research projects have shown that crowded housing lowers the quality of life and negatively impacts surrounding communities. Having more people than intended living in single-family homes or apartments strains services like trash collection, schools, and public safety. These conditions in turn are thought to lead to problems with overcrowded schools, sanitation, and higher crime and injury levels.