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Definitions and Explanations

The United States Office of Management and Budget (OMB) defines metropolitan and 

micropolitan statistical areas according to published standards that are applied to Census Bureau 

data. The general concept of a metropolitan or micropolitan statistical area is that of a core area 

containing a substantial population nucleus, together with adjacent communities having a high 

degree of economic and social integration with that core.

Standard definitions of metropolitan areas were first issued in 1949 by the then Bureau of the 

Budget (predecessor of OMB), under the designation "standard metropolitan area" (SMA). The 

term was changed to "standard metropolitan statistical area" (SMSA) in 1959, and to 

"metropolitan statistical area" (MSA) in 1983.

The term "metropolitan area" (MA) was adopted in 1990 and referred collectively to 

metropolitan statistical areas (MSAs), consolidated metropolitan statistical areas (CMSAs), and 

primary metropolitan statistical areas (PMSAs). The term "core based statistical area" (CBSA) 

became effective in 2000 and refers collectively to metropolitan and micropolitan statistical 

areas.

OMB has been responsible for the official metropolitan areas since they were first defined, 

except for the period 1977 to 1981, when they were the responsibility of the Office of Federal 

Statistical Policy and Standards, Department of Commerce. The standards for defining 

metropolitan areas were modified in 1958, 1971, 1975, 1980, 1990, 2000, and 2010.

Beginning in first quarter 2015, the Current Population Survey/Housing Vacancy Survey began

using the new metropolitan and micropolitan statistical definitions announced by OMB in 

February 2013, and were based on the application of the 2010 standards to Census 2010 data. 

The February 2013 definitions are available at: http://www.census.gov/population/metro/.

The 2015 metropolitan area data reflect 2010 definitions, the 2005 to 2014 data reflect 2000 

definitions, the 1995 to 2004 data reflect 2000 definitions, and the 1986 to 1994 data reflect 1990 

definitions. Therefore, metropolitan/nonmetropolitan data prior to 1986, 1986 to 1994, 1995 to 

2004, 2005 to 2014 and 2015 and later are not directly comparable to each other.

Defining Metropolitan and Micropolitan Statistical Areas. The term Core Based Statistical 

Area (CBSA) is a collective term for both metro and micro areas. The 2010 standards provide 

that each CBSA must contain at least one urban area of 10,000 or more population. Each 

metropolitan statistical area must have at least one urbanized area of 50,000 or more inhabitants. 

Each micropolitan statistical area must have at least one urban cluster of at least 10,000 but less 

than 50,000 population. 

Under the standards, the county (or counties) in which at least 50 percent of the population 

resides within urban areas of 10,000 or more population, or that contain at least 5,000 people 

residing within a single urban area of 10,000 or more population, is identified as a "central 

county" (counties). Additional "outlying counties" are included in the CBSA if they meet 

specified requirements of commuting to or from the central counties. Counties or equivalent 
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entities form the geographic "building blocks" for metropolitan and micropolitan statistical areas 

throughout the United States and Puerto Rico. 

If specified criteria are met, a metropolitan statistical area containing a single core with a 

population of 2.5 million or more may be subdivided to form smaller groupings of counties 

referred to as "metropolitan divisions." 

As of February 2013, there are 381 metropolitan statistical areas and 536 micropolitan statistical 

areas in the United States. 

Principal Cities and Metropolitan and Micropolitan Statistical Area. The largest city in each 

metropolitan or micropolitan statistical area is designated a "principal city." Additional cities 

qualify if specified requirements are met concerning population size and employment. The title 

of each metropolitan or micropolitan statistical area consists of the names of up to three of its 

principal cities and the name of each state into which the metropolitan or micropolitan statistical 

area extends. Titles of metropolitan divisions also typically are based on principal city names but 

in certain cases consist of county names.

Defining New England City and Town Areas. In view of the importance of cities and town in 

New England, the 2010 standards also provide for a set of geographic areas that are delineated 

using cities and towns in the six New England states. The New England city and town areas 

(NECTAs) are delineated using the same criteria as metropolitan and micropolitan statistical 

areas and are identified as either metropolitan or micropolitan, based, respectively, on the 

presence of either an urbanized area of 50,000 or more population or an urban cluster of at least 

10,000 but less than 50,000 population. If the specified criteria are met, a NECTA containing a 

single core with a population of at least 2.5 million may be subdivided to form smaller groupings 

of cities and towns referred to as New England city and town area divisions.

Changes in Definitions over Time. Changes in the delineations of these statistical areas since 

the 1950 census have consisted chiefly of the recognition of new areas as they reached the 

minimum required city or urbanized area population, and the addition of counties (or cities and 

towns in New England) to existing areas as new decennial census data showed them to qualify.

In some instances, formerly separate areas have been merged, components of an area have been 

transferred from one area to another, or components have been dropped from an area. The large 

majority of changes have taken place on the basis of decennial census data. However, Census 

Bureau data serve as the basis for intercensal updates in specified circumstances. 

Geographic regions. The four major regions of the United States for which data are presented in 

this report represent groups of States as follows:

Northeast: Connecticut, Maine, Massachusetts, New Hampshire, Rhode Island, Vermont, New 

Jersey, New York, Pennsylvania.

Midwest: Illinois, Indiana, Michigan, Ohio, Wisconsin, Iowa, Kansas, Minnesota, Missouri, 

Nebraska, North Dakota, South Dakota.
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South: Delaware, District of Columbia, Florida, Georgia, Maryland, North Carolina, South 

Carolina, Virginia, West Virginia, Alabama, Kentucky, Mississippi, Tennessee, Arkansas, 

Louisiana, Oklahoma, Texas.

West: Arizona, Colorado, Idaho, Montana, Nevada, New Mexico, Utah, Wyoming, Alaska, 

California, Hawaii, Oregon, Washington.

Housing Unit. A housing unit is a house, an apartment, a group of rooms, or a single room 

occupied or intended for occupancy as separate living quarters. Separate living quarters are those 

in which the occupants do not live and eat with other persons in the structure and which have 

direct access from the outside of the building or through a common hall. For vacant units, the 

criteria of separateness and direct access are applied to the intended occupants whenever 

possible. If the information cannot be obtained, the criteria are applied to the previous occupants. 

Tents and boats are excluded if vacant, used for business, or used for extra sleeping space or 

vacations. Vacant seasonal/migratory mobile homes are included in the count of vacant 

seasonal/migratory housing units. Living quarters of the following types are excluded from the 

housing unit inventory: Dormitories, bunkhouses, and barracks; quarters in predominantly 

transient hotels, motels, and the like, except those occupied by persons who consider the hotel 

their usual place of residence; quarters in institutions, general hospitals, and military installations 

except those occupied by staff members or resident employees who have separate living 

arrangements.

Occupied Housing Units. A housing unit is occupied if a person or group of persons is living in 

it at the time of the interview or if the occupants are only temporarily absent, as for example, on 

vacation. The persons living in the unit must consider it their usual place of residence or have no 

usual place of residence elsewhere. The count of occupied housing units is the same as the count 

of households.

Householder. The householder refers to the person (or one of the persons) in whose name the 

housing unit is owned or rented or, if there is no such person, any adult member, excluding 

roomers, boarders, or paid employees. If the house is jointly owned by a married couple, either 

the husband or the wife may be listed first, thereby becoming the reference person, or 

householder, to whom the relationship of the other household members is recorded. One person 

in each household is designated as the "householder."

Vacant Housing Units. A housing unit is vacant if no one is living in it at the time of the 

interview, unless its occupants are only temporarily absent. In addition, a vacant unit may be one 

which is entirely occupied by persons who have a usual residence elsewhere. New units not yet 

occupied are classified as vacant housing units if construction has reached a point where all 

exterior windows and doors are installed and final usable floors are in place. Vacant units are 

excluded if they are exposed to the elements, that is, if the roof, walls, windows, or doors no 

longer protect the interior from the elements, or if there is positive evidence (such as a sign on 

the house or block) that the unit is to be demolished or is condemned. Also excluded are quarters 

being used entirely for nonresidential purposes, such as a store or an office, or quarters used for 

the storage of business supplies or inventory, machinery, or agricultural products. Vacant 

sleeping rooms in lodging houses, transient accommodations, barracks, and other quarters not 
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defined as housing units are not included in the statistics in this report. (See section on "Housing 

Unit.") 

Year-round Vacant Units. Beginning in 1990, year-round vacant mobile homes were included 

as part of the year-round vacant count of housing units. Year-round units are those intended for 

occupancy at any time of the year, even though they may not be in use the year round. In resort 

areas, a housing unit which is usually occupied on a year-round basis is considered a year-round 

unit. As indicated above, year-round units temporarily occupied by persons with usual residence 

elsewhere are included with year-round vacant units. 

Year-round vacant units are classified in the following categories:

Vacant units for rent. This group consists of vacant units offered for rent and those offered both 

for rent and sale.

Vacant units for sale only. This group is limited to units for sale only; it excludes units both for 

rent and sale. If a unit was located in a multi-unit structure which was for sale as an entire 

structure and if the unit was not for rent, it was reported as "held off market." However, if the 

individual unit was intended to be occupied by the new owner, it was reported as "for sale."

Vacant units rented or sold. This group consists of year-round vacant units which have been 

rented or sold but the new renters or owners have not moved in as of the day of interview. 

Vacant units held off the market. Included in this category are units held for occasional use, 

temporarily occupied by persons with usual residence elsewhere, and vacant for other reasons. 

These classifications are described below.

For occasional use. If the vacant unit is not for-rent or for-sale-only but is held for weekends or 

occasional use throughout the year, the unit is included in this category. Time-shared units are 

classified in this category if the vacant unit is not for-rent or for-sale-only, but held for use for an 

individual during the time of interview.

Units Occupied by Persons With Usual Residence Elsewhere. A housing unit which is 

occupied temporarily by persons who usually live elsewhere is interviewed as a vacant unit 

provided that a usual place of residence is held for the household which is not offered for rent or 

for sale. For example, a beach cottage occupied at the time of the interview by a family which 

has a usual place of residence in the city is included in the count of vacant units. Their house in

the city would be reported "occupied" and would be included in the count of occupied units since 

the occupants are only temporarily absent. Units occupied by persons with usual residence 

elsewhere (URE) are further classified as seasonal vacant or year round vacant units. 

Other vacant. Included in this category are year-round units which were vacant for reasons 

other than those mentioned above: For example, held for settlement of an estate, held for 

personal reasons, or held for repairs. Below are the definitions for the other vacant categories 

presented in Historical Table 18. 
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 Foreclosure. This category is for units that are vacant because owners’ payments 

(mortgage, taxes, or loans) to their lending institution, city, or state, were no longer being 

made. Includes units that are under foreclosure, bank owned, bankrupt, up for auction, 

sheriff’s sale, repossessed, have a lien, or taken for taxes. 

 Personal/Family Reasons. This category is for units that are vacant due to the owners’ 

preferences and/or personal situation. Includes units where the owner does not want to 

rent/sell, owner is deciding what to do, owner is keeping for family use, owner is staying 

with family, or owner is in assisted living or other type of care situation.

 Legal Proceedings. This category is for units that are vacant due to legal issues or 

disputes. Includes units held for the settlement of estate, in probate, involved in divorce 

or eviction proceedings, or where the owner is deceased. Also includes units with code 

violations.

 Preparing to Rent/Sell. This category is for units that are vacant and the owner is 

currently preparing to rent or sell. Includes units that will be placed for rent or for sale 

this month or where the owner is meeting with a listing agent/agency this month to 

prepare to put the unit on the market.

 Held for Storage of Household Furniture. This category is for units that are vacant and 

used to store excess household furniture or other household items.

 Needs Repairs. This category is for units that are vacant and in need of repairs. Includes 

units that are in need of repair, renovations, or cleaning, but are not currently being 

repaired, renovated, or cleaned.

 Currently Being Repaired/Renovated. This category is for units that are vacant and 

currently undergoing repairs. Includes units that are being repaired, renovated, 

refurbished, or cleaned.

 Specific Use Housing. This category is for units that are vacant and only used by a 

specific group of people at one or various times throughout the year. Includes military 

housing, employee/corporate housing, transient quarters, units held by a church, student 

housing (dorms and school-sponsored housing), model home/apartment, or guest house.

 Extended Absence. This category is for units that are intended for year-round occupancy 

but are vacant for 6 months or more. Includes units where the owner is on extended work 

or military assignment, temporarily out of the country, or in jail or other type of detention 

situation.

 Abandoned/Possibly to be Demolished/Possibly Condemned. This category is for units 

that are vacant and abandoned, to be demolished, or condemned. Includes units that are 

abandoned. Also includes units that are said to be demolished or condemned, but where 

there is no positive evidence such as a sign, notice, or mark on the house or in the block 

to indicate the unit is to be demolished or condemned.

 Other Write-in/Don’t Know. This category is for units that are vacant for reasons that 

do not fit into any of the above categories. This category also includes units where the 

knowledgeable respondent and/or field representative does not know why the unit is other 

vacant.
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Seasonal Vacant Units. Seasonal housing units are those intended for occupancy only during 

certain seasons of the year and are found primarily in resort areas. Housing units held for 

occupancy by migratory labor employed in farm work during the crop season are tabulated as 

seasonal. As of the first quarter 1986 vacant seasonal mobile homes are being counted as a part 

of the seasonal housing inventory. 

Vacancy and Homeownership Rates. In this report several measures are shown for vacant 

housing units that are on the market for rent or for sale only. Measures are also shown for 

homeownership rates. 

Rental Vacancy Rate. The rental vacancy rate is the proportion of the rental inventory which is 

vacant for rent. In tables 1 and 2, the rates are computed using the following formula:

Rental Vacancy Rates by Selected Characteristics. The rental vacancy rates shown in table 3 

are the percent relationship of the vacant year- round units for rent with a specific characteristic 

(such as 3-room units) to all rental units with that specific characteristic. Excluded from the 

denominator are year-round units rented but awaiting occupancy. The rates are computed as 

follows:

For example, the numerator for the rental vacancy rate for units with 3 rooms is all vacant yearround for rent units with 3 rooms. The denominator is: (1) all renter occupied units with 3 rooms 

and (2) vacant year-round units for rent with 3 rooms. 

Homeowner Vacancy Rate. The homeowner vacancy rate is the proportion of the homeowner 

inventory which is vacant for sale. In tables 1 and 2, the rates are computed using the following 

formula: 
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Homeowner Vacancy Rates by Selected Characteristics. The homeowner vacancy rates 

shown in table 3 are the percent relationship of the vacant year-round units for sale with a 

specific characteristic (such as 3-room units) to all homeowner units with that specific 

characteristic. Excluded from the denominator are year-round units sold but awaiting occupancy. 

The rates are computed as follows:

For example, the numerator for the homeowner vacancy rate for units with 3 rooms is all vacant 

year-round units for sale only with 3 rooms.

The denominator is: (1) all owner occupied units with 3 rooms and (2) vacant year-round units 

for sale with 3 rooms.

Homeownership Rates. The proportion of households that are owners is termed the 

homeownership rate. It is computed by dividing the number of households that are owners by the 

total number of occupied households (table 5 and 6). The formula is as follows:

Homeownership by Age of Householder. This homeownership rate is calculated by dividing 

the number of owner household in a particular age group by the total number of occupied 

households in that age group (table 7).

Other Occupancy and Vacancy Rates. The percent distribution of vacant and occupied

housing units, shown in tables 10 and 11, are shown as a percent of all housing units and are 

computed using the following formula.

For example, the numerator for the for-rent rate is all year-round vacant units for rent. The 

denominator is all housing units. 
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Tenure. A unit is owner occupied if the owner or co-owner lives in the unit, even if it is 

mortgaged or not fully paid for. A cooperative or condominium unit is "owner occupied" only if 

the owner or co-owner lives in it. All other occupied units are classified as "renter occupied," 

including units rented for cash rent and those occupied without payment of cash rent.

Number of Rooms. Included in the count of rooms were whole rooms such as living rooms, 

dining rooms, bedrooms, kitchens, finished basements or attics, recreation rooms, permanently 

enclosed sun porches which are suitable for year-round use, and lodger's rooms. A partially 

divided room, such as dinette next to a kitchen or living room was counted as a separate room 

only if there was a partition from floor to ceiling, but was not counted as a room if the partition 

consisted solely of shelves or cabinets. Not included in the count of rooms were bathrooms, 

halls, foyers or vestibules, balconies, closets, alcoves, pantries, strip or pullman kitchens, laundry 

or furnace rooms, unfinished attics or basements, open porches, sun porches not suited for yearround use, unfinished space used for storage, mobile homes or trailers used only as bedrooms, 

and offices used only by persons not living in the unit. A room used by the occupants of more 

than one unit was included with the unit from which it could be most easily reached. The median 

number of rooms is the theoretical value which divides the housing units equally, one-half 

having more rooms and one-half having fewer rooms than the median. In the computation of the 

median, a continuous distribution was assumed. For example, when the median was in the threeroom group, the lower and upper limits were assumed to be 2.5 and 3.5, respectively. Tenths 

were used in the computation of the median to permit comparisons. 

Number of Bedrooms. Rooms used mainly for sleeping, even if used for other purposes, were 

counted as bedrooms. Also included in the count of bedrooms were rooms reserved for sleeping, 

such as guest rooms, even though used infrequently. A room used mainly for other purposes, 

although also used for sleeping, such as a living room with a hide-away bed, was not counted as 

a bedroom. A one-room apartment, therefore, was reported as having no bedroom. 

Number of Housing Units in Structure. A structure is a separate building which either has 

open space on all four sides or is separated from other structures by dividing walls that extend 

from ground to roof. In double houses, row houses, and houses attached to nonresidential 

structures, each building is a structure if the common wall between them goes from ground to 

roof. Sheds and private garages which adjoin houses are not counted as separate structures. In 

apartment developments, each building with open space on all sides is considered a separate 

structure. The count of housing units in a structure is the total number of units in the structure, 

both occupied and vacant units. In the tabulations, occupied mobile homes or trailers, tents, and 

boats are included in the category one housing unit in structure. 

The statistics reflect the number of housing units in the structure in which they are located, rather 

than the number of residential structures. In the quarterly surveys, data were obtained on the 

number of housing units in the structure, regardless of the type of structures in which the unit 

was located.

Year Structure Built. "Year structure built" refers to the date the original construction of the 

structure was completed, and not to any later remodeling, addition, or conversion. The figures on 
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the number of units built during a given period relate to the number of units in existence at the 

time of interview. For both occupied and vacant mobile homes, "model year" is the year built.

Duration of Vacancy. The length of time a housing unit was vacant was computed from the day 

the unit became vacant until the day of the interview. The data, therefore, do not provide a direct 

measure of the total length of time units remain vacant. For newly constructed units, the duration 

of vacancy represents the time period since the date when the unit was considered a vacant 

housing unit, that is, when construction had reached the point that all exterior windows and doors 

were installed and final usable floors were in place. For recently converted or merged units, the 

length of time is reported from the date the conversion or merger was completed. For units 

temporarily occupied by persons with a usual residence elsewhere, duration of vacancy is the 

length of time since the last usual residents moved; if the unit was always occupied by persons 

with usual residence elsewhere the time is reported from the date the unit was originally ready 

for occupancy. The time intervals used in the tables represent full months, calculated from a date 

in the month to the same date the following month. For example, if the unit became vacant on 

July 29 and was still vacant on the day interviewed, September 20, the time reported would be "1 

to 2 months," meaning that the unit had been vacant for more than 1 month but less than 2 

months. Or if the unit became vacant on August 25 and was still vacant on September 20, the 

time reported would be "less than 1 month." 

Previous Occupancy. A unit was classified as being "previously occupied" if the unit had ever 

been occupied or if the unit was occupied by persons with a usual residence elsewhere. If a 

previously occupied unit had been converted into several housing units, each unit was classified 

as being previously occupied. Also, housing units that resulted from conversion of nonresidential 

space or from a merger was reported as being previously occupied. Only vacant newly 

constructed units were classified as "not previously occupied." 

Contract Rent. For renter-occupied units, the contract rent is the monthly rent agreed upon 

regardless of any furnishings, utilities, or services that may be included. For vacant units, rent is 

the amount asked for the unit at the time of interview; the amount may differ from the rent 

contracted for when the unit is occupied. Data for contract rent excludes units for which no cash 

rent is paid. As in the 1980 census, the statistics are limited to specified rental units. These data 

exclude rents for renter-occupied and vacant for-rent single-family structures on places of 10 

acres or more. The median monthly rent is the rent which divides the series into two equal parts, 

one-half of the units with rents higher than the median and the other half with rents lower than 

the median. In the computation of the median, a continuous distribution was assumed, and the 

limits of the class intervals were assumed to stand at the midpoint of the 1-dollar interval 

between the end of one of the rent groups and the beginning of the next. For example, the limits 

of the interval designated $250 to $299 were assumed to be $249.50 and $299.50.

Inclusion of Utilities in Rent. The utilities included in the inquiry were electricity, gas, water, 

oil, coal, wood, and kerosene, etc. The statistics reflect whether all or some or none of these 

utilities are provided for in the amount of rent asked at the time of the interview. A unit was 

classified as having "all utilities included" if the cost of the utilities are included in the rent at no 

additional cost to the renter or if the utilities would not be used by the renter. A unit was 

classified as having "some or none included" if all or part of the utilities are to be paid for 
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separately by the renter in addition to the rent asked. Data on the inclusion of utilities are limited 

to vacant units for which rent is reported. No data on utilities are collected for renter-occupied 

units.

Value. Value is the respondent's estimate of how much the property would sell for on the current 

market. For vacant units, value is the sales price asked for the property at the time of the 

interview and may differ from the price at which the property is sold. The "sales price asked" 

includes the price of a one-housing-unit structure and the land on which it is located. The "sales 

price asked" may also include additional structures such as garages, sheds, barns, etc.

In this report, statistics on value for owner-occupied units and vacant for-sale-only units are 

limited to specified homeowner units which includes all one-housing unit structures located on 

places of less than 10 acres, without a commercial establishment or medical office on the 

property and with only one-housing unit on the property. The median value or sales price is the 

amount which divides the series into two equal parts, one-half of the units with values higher 

than the median and the other half with values lower than the median. The median was computed 

on the basis of more detailed tabulation groups than are shown in the tables and was rounded to 

the nearest hundred dollars.

Family. A family is a group of two persons or more (one of whom is the householder) related by 

birth, marriage, or adoption and residing together; all of such persons (including related 

subfamily members) are considered as members of one family. Beginning with the 1980 CPS, 

unrelated subfamilies (referred to in the past as secondary families) are no longer included in the 

count of families, nor are the members of unrelated subfamilies included in the count of family 

members.

Married-Couple Families. A married couple, as defined for Census purposes, is a husband and 

wife enumerated as members of the same household. The married couple may or may not have 

children living with them. The expression "husband-wife" or "married-couple" before the term 

"household," or "family," indicates that the household, or family, is maintained by a husband and 

wife.

Other Family Households

Male Householder no wife present: This category includes households with male householders 

who are married with at least one other relative in the household, but with wife absent because of 

separation or other reason where husband and wife maintain separate residences; and male 

householders who are widowed, divorced, or single with at least one other relative in the 

household.

Female Householders no husband present: This category includes households with female 

householders who are married with one other relative in the household, but with husband absent 

because of separation or other reason where husband and wife maintain separate residences; and 

female householders who are widowed, divorced, or single with at least one other relative in the 

household.
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Non-family householder. A non-family householder is a person maintaining a household while 

living alone or with non-relatives only.

One-person Households. Households consisting of only one person are shown separately for 

male householder and female householder under the category "one-person households".

Other Two-or-More-Person Households. Households consisting of a householder living with 

one or more non-relatives only. Data are shown separately for male and female householder 

only.

Single Male Householder. This includes the following 3 categories--other family householdsmale householder no wife present, one person male householder, and Nonfamily Other Two-orMore-Person Male Households.

Single Female Householder. This includes the following 3 categories--other family householdsfemale householder no husband present, one person female householder, and Nonfamily Other 

Two-or-More-Person female Households.

Age. The age classification is based on the age of the householder at the time of interview.