The data on vacancy status were obtained from Enumerator Questionnaire item C. Vacancy status and other characteristics of vacant units were determined by census enumerators obtaining information from landlords, owners, neighbors, rental agents, and others. Vacant units are subdivided according to their housing market classification as follows:

    For Rent - These are vacant units offered for rent and vacant units offered either for rent or for sale.
    Rented, Not Occupied - These are vacant units rented but not yet occupied, including units where money has been paid or agreed upon, but the renter has not yet moved in.
    For Sale Only - These are vacant units being offered for sale only, including units in cooperatives and condominium projects if the individual units are offered for sale only. If units are offered either for rent or for sale, they are included in the for rent classification.
    Sold, Not Occupied - These are vacant units sold but not yet occupied, including units that have been sold recently, but the new owner has not yet moved in.
    For Seasonal, Recreational, or Occasional Use - These are vacant units used or intended for use only in certain seasons or for weekends or other occasional use throughout the year. Seasonal units include those used for summer or winter sports or recreation, such as beach cottages and hunting cabins. Seasonal units also may include quarters for such workers as herders and loggers. Interval ownership units, sometimes called shared-ownership or time-sharing condominiums, also are included here.
    For Migrant Workers - These include vacant units intended for occupancy by migratory workers employed in farm work during the crop season. (Work in a cannery, freezer plant, or food-processing plant is not farm work.)
    Other Vacant - If a vacant unit does not fall into any of the categories specified above, it is classified as Other vacant. For example, this category includes units held for occupancy by a caretaker or janitor and units held for personal reasons of the owner.
    Homeowner Vacancy Rate - The homeowner vacancy rate is the proportion of the homeowner inventory that is vacant for sale. It is computed by dividing the number of vacant units for sale only by the sum of the owner-occupied units, vacant units that are for sale only, and vacant units that have been sold but not yet occupied, and then multiplying by 100. This measure is rounded to the nearest tenth.
    Rental Vacancy Rate - The rental vacancy rate is the proportion of the rental inventory that is vacant for rent. It is computed by dividing the number of vacant units for rent by the sum of the renter-occupied units, vacant units that are for rent, and vacant units that have been rented but not yet occupied, and then multiplying by 100. This measure is rounded to the nearest tenth.
    Available Housing Vacancy Rate - The available housing vacancy rate is the proportion of the housing inventory that is vacant-for-sale only and vacant-for-rent. It is computed by dividing the sum of vacant-for-sale-only housing units and vacant-for-rent housing units, by the sum of occupied units, vacant-for-sale-only housing units, vacant-sold-not-occupied housing units, vacant-for-rent housing units, and vacant-rented-not-occupied housing units, and then multiplying by 100. This measure is rounded to the nearest tenth.
    Comparability - Data on vacancy status have been collected since 1940. Since 1990, we have used the category For seasonal, recreational, or occasional use. In earlier censuses, separate categories were used to collect data on these types of vacant units. Also, in 1970 and 1980, housing characteristics generally were presented only for year-round units. Beginning in 1990 and continuing into Census 2000, housing characteristics are shown for all housing units. Census 2000 used a single vacancy status category for units that were either Rented or sold, not occupied. In 2010, we used two separate categories Rented, not occupied and Sold, not occupied. This change provided consistency with the American Community Survey and the Housing Vacancy Survey. These revised categories were incorporated in the calculations of the homeowner vacancy, rental vacancy, and the available housing vacancy rates.