A common measure of community-wide affordability is the number of homes that a household with a certain percentage of median income can afford. For example, in a perfectly balanced housing market, the median household (and the half of the households which are wealthier) could officially afford the median housing option, while those poorer than the median home could not afford the median home. 50% affordability for the median home indicates a balanced market.
A community might track the percentage of its housing that is affordable to households earning 60% of median income. In addition to the distress it causes families who cannot easily find a place to live, lack of affordable housing is considered by many urban planners to have negative effects on a community's overall health. For example, lack of affordable housing can make low-cost labor more scarce, and increase demands on transportation systems (as workers travel longer distances between jobs and affordable housing). A number of studies and articles focused on U.S. cities (Los Angeles, CA, Sarasota, FL) seek to link housing cost increases and declines in enrollment at local schools.