100-percent Data (see also Short Form and Long Form)
The term "100-percent data" refers to census information collected for every person and housing unit in the U.S. The Census Bureau gathers the data based on a limited number of basic population and housing questions that are included both the short form and the long form of the census questionnaire.

Ability to Speak English (see also Language Spoken at Home)
The census questionnaire asked people who reported speaking a language other than English at home, or who had members of their household who spoke a different language at home, to rate that person’s ability to speak English. Possible responses ranged from "very well" to "not at all."

Age
Age is based on a person’s date of birth and discounted in complete years as of April 1, 2000.

Aggregate
An aggregate is the sum of all the values for a particular item. For example, the aggregate population of Virginia would be the sum of the populations of all of its cities and counties.

Ancestry
Ancestry refers to a person’s ethnic origin or heritage, or the place of birth of that person or their parents or ancestors before their arrival in the United States. Individuals identified their own ancestry on the census questionnaire by choosing the group or groups that they found most appropriate The question allowed respondents to report one or more ancestry groups; however, the Census Bureau only tabulated the first two responses.

Apportionment Population (see also Resident Population)
The apportionment population is the population counted by the Census Bureau used to distribute seats in the House of Representatives among the states. It consists of two groups:

(1) the resident population of the 50 states and
(2) US Armed Forces personnel and federal civilian employees stationed outside the United States (and their dependents living with them) that can be allocated back to a home state.

The apportionment population does not include the population residing in Washington, D.C. or any of the US territories.

Area (see also Population Density)
The Census Bureau calculates land, water, and total areas for all the geographic divisions for which it tabulates data. The Bureau uses TIGER, a geographic database, and the boundaries it has recorded to make the calculations.

For further information, please see:
http://www.census.gov/geo/www/tiger/glossary.html#AreaMeasurement

Armed Forces
The category "Armed Forces" includes people on active duty with the United States Army, Air Force, Navy, Marine Corps, or Coast Guard who are stationed in the United States. It does not include members of these military branches who are stationed in foreign countries.

Average
An average is found by dividing the sum of all the values in a category by the total number of items in that category. For example, average family size is found by dividing the total number of people living in families by the total number of families.

Barracks (see Group Quarters Population)

Bedrooms
A bedroom is a room used mainly for sleeping. Rooms reserved for sleeping, such as guest rooms, are counted as bedrooms even if they are used infrequently. The Census Bureau does not consider rooms used mainly for other purposes, such as a living room with a hideaway bed, to be bedrooms. A housing unit consisting of only one room, such as a one-room efficiency apartment, is classified as having no bedroom.

Born at Sea (see also Foreign Born & Native)

Census Designated Place (see also Incorporated Place)
The Census Bureau designates two types of places: incorporated places, such as cities and counties, and census designated places (CDP’s). CDPs are the statistical counterparts of incorporated places—they comprise densely settled concentrations of population that are identifiable by name, but are not legally incorporated. A CDP’s boundaries have no legal status, and the CDP does not have elected officials.

Census Tract
Census tracts are small, relatively permanent statistical subdivisions of a county or independent city.

Local committees establish the tract boundaries using Census Bureau guidelines. Each tract contains, on average, about 4,000 inhabitants. Tracts are designed so that their residents have similar population characteristics, economic status, and living conditions. The committees create tract boundaries with the intention that they can be maintained over time, thus enabling statistical comparisons from one census to another. Nonetheless, 2000 census tracts are often not comparable to those used in 1990. You can find maps of the 1990 tracts on American Factfinder. Maps of 2000 census tracts are available in American Factfinder and on this site.

This website only includes census tract information for Summary File 1. For census tract information from Summary File 3 see the Census Bureau's American Factfinder site.

For further information about census tracts, see:
http://www.census.gov/geo/www/cen_tract.html

Child
The Census Bureau defines a child as a son or daughter by birth, a stepchild, or an adopted child of the householder, regardless of the child’s age or marital status.

Citizenship Status (see also Native & Foreign Born)
The Census Bureau classifies people living in the United States as citizens or noncitizens. People become citizens anion of the following ways: 1) being born in the Unites States, (2) being born in a foreign country to at least one parent who is an American citizen, or (3) completing the naturalization process to become a US citizen. A resident who is not a citizen is classified as a noncitizen.

Class of Worker
Private wage and salary workers - People who work for wages, salary, commission, or tips from a private employer. The employer can be for-profit or not-for-profit. The Census Bureau includes self-employed workers whose business is incorporated in this group.

Government workers - People who work for a local, state, or federal government agency as well as foreign governments and international governmental organizations such as the United Nations.

Self-employed workers - People who work for profit in their own business, trade, or farm.

Unpaid family workers - People who work 15 hours or more without pay in a business or farm operated by a relative.

Commuting to Work
Means of transportation to work refers to the way that a worker usually used to get from home to work during the reference week. The reference week is the full calendar week proceeding the date on which the person completed the census questionnaire. The category "Car, truck, or van — drove alone" includes people who usually drove alone to work, as well as people who were driven to work by someone who then drove back home. The category "Car, truck, or van — carpooled" includes workers who rode to work with one or more other people in a vehicle during the reference week. The category "Public transportation (including taxicab)" includes workers who usually used a bus, streetcar, subway, railroad, ferryboat, or taxicab during the reference week.

Contract Rent
Contract rent is the monthly rent agreed to for a rental unit, regardless of any furnishings, utilities, fees, meals, or services that may be included. For vacant units, the contract rent is the monthly rent asked for the rental unit at the time of the census.

Disability Status
The Census Bureau considers people 5 years old and over to have a disability if they have one or more of the following: (a) blindness, deafness, or a severe vision or hearing impairment; (b) a substantial limitation in the ability to perform basic physical activities, such as walking, climbing stairs, reaching, lifting, or carrying; (c) difficulty learning, remembering, or concentrating; or (d) difficulty dressing, bathing, or getting around inside the home. In addition to the above criteria, the bureau considers people 16 years old and over to have a disability if they have difficulty going outside the home alone to shop or visit a doctor’s office. People 16-64 years old are considered to have a disability if they have difficulty working at a job or business.

Dormitories (see Group Quarters Population)

Earnings
Earnings is defined as the sum of wage and salary income from employment and net income from self-employment. Earnings represent the amount of income received regularly before deductions for personal income taxes, social security, bond purchases, union dues, Medicare deductions, etc.

Educational Attainment
Educational attainment refers to the highest level of school completed or the highest level of degree obtained by a person. The highest level of schooling completed is measured by grade level. The highest level of degree obtained may be a high school diploma, associate's degree, bachelor's degree, master's degree, doctorate, or a professional degree in a field such as medicine, law, or theology. Vocational and technical training is not included in educational attainment.

Employed (see also Labor Force & Unemployed)
The Census Bureau considers people over the age of 16 to be employed if they are either "at work" or "with a job, but not at work." "At work" refers to people who did any work during the reference week as paid employees, worked in their own business or profession, worked on their own farm, or worked 15 hours or more as unpaid workers on a family farm or in a family business. "With a job, but not at work" includes people who did not work during the reference week, but had jobs or businesses from which they were temporarily absent. Excluded from the employed are people whose only activity consisted of repair work or housework around their homes or unpaid volunteer work for religious or charitable organizations. Also excluded are people on active duty in the US Armed Forces. The reference week is the full calendar week proceeding the date on which the respondent completed the census questionnaire.

Ethnicity (see also Race)
Ethnicity refers to whether a person is of Hispanic, Latino or Spanish origin or descent. Ethnicity is independent of race, and a Hispanic person may be of any race. Persons identifying themselves as Hispanic in the census were then asked to specify further their ethnic origin in one of four categories: (1) Mexican, Mexican American, or Chicano; (2) Puerto Rican; (3) Cuban; and (4) Other.

Family Household, or Family (see also Household)
A family includes a householder and one or more people living in the same household who are related to the householder by birth, marriage, or adoption. All people in a household who are related to the householder are counted as members of his or her family. A family household may contain people not related to the householder (such as a boarder), but those people are not included as part of the householder’s family in census tabulations. A household can contain only one family for purposes of census tabulations. Not all households contain families since a household may comprise a group of unrelated people or one person living alone.

Family Income (see also Income in 1999)
Family income is the sum of the incomes of all the members of a family who are 15 years old and older.

Foreign Born
The Census Bureau uses two main categories to classify people according to their place of birth: Native and Foreign born. Native includes people born in the United States, Puerto Rico, or outlying areas of the United States, and those who were born overseas but have at least one American parent. Foreign born includes all other people born in foreign countries. Although the bureau has asked about this information in previous censuses, the results have been reported in different ways and the data are not comparable over time. To learn more about interpreting foreign-born data over time, see this Census Bureau publication.

Full-time, Year-round Workers
Full-time, year-round workers are people 16 years old and over who usually worked 35 hours or more per week for 50 to 52 weeks in 1999.

Grandparents as Caregivers
The Census Bureau collects data on whether a grandchild lives in the household of a grandparent, whether that grandparent has responsibility for the basic needs of the grandchild, and the duration of that responsibility. The data on grandparents as caregivers were derived from answers to questions asked of the population 15 years and over, but because very few people under 30 years old are grandparents data are only shown for people 30 years old and over.

Gross Rent (see also Specified Renter-Occupied Units)
Gross rent is the monthly contract rent for a housing unit, plus the estimated average monthly cost of utilities and fuels if the renter pays these.

Group Homes (see Group Quarters Population)

Group Quarters Population
The group quarters population includes all people not living in households. This population is divided into two categories: (1) the institutionalized population, which includes people under formally supervised care or custody in institutions such as correctional facilities, nursing homes, and juvenile institutions, and (2) the noninstitutionalized population, which includes all people who live in group quarters other than institutions, such as college dormitories, military quarters (barracks), and group homes. The group quartered population is included in the census figures for the locality of the facility where they live.

Hispanic or Latino (see also Ethnicity and Race)
"Hispanic or Latino" refers to people who classify their ethnic origin as Hispanic or Latino. Origin can be viewed as the heritage, nationality group, lineage, or country of birth of the person or the person’s parents or ancestors before their arrival in the United States. People who identify their origin as Hispanic or Latino may be of any race.

Homeowner Vacancy Rate (see also Vacancy Status)
The homeowner vacancy rate is the percentage of homeowner housing units that are vacant and for sale at one time. It is calculated by dividing the number of vacant units for sale by the sum of owner-occupied units and vacant units that are for sale, and then multiplying by 100.

Hospitals (see also Group Quarters Population)

House Heating Fuel
House heating fuel is the type of fuel used most often to heat a housing unit.

Household
A household includes all of the people who occupy a housing unit. People not living in households are classified as living in group quarters.

Household Income (see also Income in 1999)
Household income includes the income of the householder and all other individuals 15 years old and over in the household, whether they are related to the householder or not. Because many households consist of only one person, average household income is usually less than average family income.

Household Size
A household consists of all people who occupy a particular housing unit as their usual residence, or who live there at the time of the interview and have no usual residence elsewhere. A usual residence is the place where a person lives and sleeps most of the time. Households include not only occupants related to the householder but also any lodgers, roomers, boarders, partners, wards, foster children, and resident employees who share the living quarters of the householder. They include people temporarily away for reasons such as visiting, traveling in connection with jobs, in general hospitals, and in other temporary locations.

Household Type and Relationship
The Census Bureau classifies households by type according to the sex of the householder and the presence of relatives. Examples of household types are households headed by a married couple, households with a male householder and no wife present; and households with a female householder and no husband present. Household relationships are defined by that person’s relationship to the head of household and include husband, wife, child, and other relative.

Householder
In most cases the householder is the person, or one of the people, in whose name the home is owned, being bought, or rented and who is listed as "Person 1" on the census questionnaire. If there is no such person in the household, any adult household member 15 years old and over can be designated as the householder.

Housing Unit
A housing unit may be a house, an apartment, a mobile home, a group of rooms, or a single room that is occupied as separate living quarters (or if it is vacant, is intended for occupancy). Separate living quarters are those in which the occupants live separately from any other individuals in the building and which have direct access from outside the building or through a common hall.

Income in 1999 (see also Income Type in 1999)
The census questionnaire requested information on income received in the calendar year 1999 from individuals 15 years and over. Total income is the sum of the amounts reported separately for wage or salary income; net self-employment income; interest, dividends, or net rental or royalty income; social security or railroad retirement income; supplemental security income (SSI); public assistance or welfare payments; retirement or disability income; and all other income.

Receipts from the following sources are not included as income: money received from the sale of property (unless the recipient was engaged in the business of selling such property); capital gains; the value of income "in kind" from food stamps, public housing subsidies, medical care, employer contributions for individuals, etc.; withdrawal of bank deposits; money borrowed; tax refunds; exchange of money between relatives living in the same household; and gifts and lump-sum inheritances, insurance payments, and other types of lump-sum receipts.

Although the income statistics cover calendar year 1999, the characteristics of individuals and the composition of households/families refer to the time of enumeration (April 1, 2000). Thus, the income of the household or family does not include amounts received by individuals who were members of the household/family during all or part of 1999 if these individuals no longer resided with the household/family at the time of enumeration. Similarly, income amounts reported by individuals who did reside with the household/family at the time of enumeration are included even if they did not reside with the household or family in 1999. However, the composition of most households/families was the same during 1999 as at the time of enumeration.

Income Type in 1999 (see also Income in 1999)
Wage or salary income includes total money earnings received for work performed as an employee during calendar year 1999. It includes wages, salary, Armed Forces pay, commissions, tips, piece-rate payments, and cash bonuses earned before deductions were made for taxes, bonds, pensions, union dues, etc.

Self-employment income includes both farm and nonfarm self-employment income:

nnNon-Farm self-employment income includes net money income (gross receipts minus expenses) from one’s own business, professional enterprise, or partnership. Gross receipts include the value of all goods sold and services rendered. Expenses include costs of goods purchased, rent, heat, light, power, depreciation, charges, wages and salaries paid, business taxes (not personal income taxes), etc.

nnFarm self-employment income includes net money income (gross receipts minus operating expenses), from the operation of a farm by a person on his or her own account, as an owner, renter, or sharecropper. Gross receipts include the value of all products sold; government farm programs; money received from the rental of farm equipment to others; and incidental receipts from the sale of wood, sand, gravel, etc. Operating expenses include cost of feed, fertilizer, seed, and other farming supplies; cash wages paid to farmhands; depreciation charges; cash rent; interest on farm mortgages; farm building repairs; farm taxes (not state and federal personal income taxes), etc. Net income does not include the value of fuel, food, or other farm products used for family living.

Interest, dividends, or net rental income includes interests on savings or bonds, dividends from stockholdings or membership in associations, net income from rental of property to others and receipts from boarders or lodgers, net royalties, and periodic payments from an estate or trust fund.

Social security income includes social security pensions, survivors’ benefits, and permanent disability insurance payments made by the Social Security Administration prior to deductions for medical insurance. It also includes railroad retirement insurance checks from the US government. It does not include Medicare reimbursements.

Supplemental security income is a US federal assistance program administered by the Social Security Administration that guarantees a minimum level of income for needy aged, blind, or disabled individuals.

Public assistance income includes general assistance and temporary assistance to needy families (TANF). Separate payments received for hospital or other medical care (vendor payments) are excluded. Public assistance income does not include supplemental security income.

Retirement or disability income includes: (1) retirement pensions and survivor benefits from a former employer; labor union; or federal, state, or local government; and the US military; (2) income from workers’ compensation; disability income from companies or unions; federal, state, or local government; and the US military; (3) periodic receipts from annuities and insurance; and (4) regular income from IRA and KEOGH plans. Retirement or disability income does not include social security income.

All other income includes unemployment compensation, Veterans’ Administration payments, alimony and child support, contributions received periodically from people not living in the household, military family allotments, and other kinds of periodic income other than earnings.

Incorporated Place (see also Census Designated Place)
An incorporated place is, depending on the state, either a city, town, borough, or village. In Virginia there are two kinds of incorporated places - independent cities and towns. Both independent cities and towns have legally defined boundaries and elected officials. Click here for a list of Virginia's incorporated towns and cities.

Industry
Information on industry refers to the kind of business conducted by a person’s employer. For people who worked at two or more jobs, the data refer to the job at which the person worked the greatest number of hours. Some examples of types of industry include agriculture, forestry, fishing and hunting, and mining; construction; manufacturing; wholesale trade; retail trade; and public administration.

Institutionalized Population (see Group Quarters Population)

Jails (see Group Quarters Population)

Kitchen Facilities
Complete kitchen facilities include all of the following: a sink with running water, a range or cook top and oven, and a refrigerator. All kitchen facilities must be located in the housing unit, but not necessarily in the same room.

Labor Force (see also Employed and Unemployed)
The labor force includes all persons classified as being in the civilian labor force (that is, "employed" and "unemployed" persons), plus members of the US Armed Forces—people on active duty in the Army, Air Force, Navy, Marine Corps, and Coast Guard.

Language Spoken at Home (see also Ability to Speak English)
The Census Bureau classifies as speaking a language other than English those persons who report that they "sometimes" or "always" speak a non-English language at home. It excludes those who speak a language other than English only at school or at work. It also excludes those who speak only a few expressions or slang in a non-English language.

Living Quarters
Living quarters are either housing units or group quarters.

Long Form
The long form is the expanded census questionnaire, sent to approximately one in six households for the 2000 census. The long form contained all of the questions on the short form, as well as additional detailed questions relating to the social, economic, and housing characteristics of each individual and household. See short form.

Marital Status
The census questionnaire asked each person whether they were "now married," "widowed," "divorced," "separated," or "never married." Couples who lived together were able to report the marital status they considered the most appropriate.

Meals Included in Rent
Meals included in rent refers to whether or not any meals are provided as part of the rent for a housing unit. The Census Bureau uses the data to measure "congregate" housing, which is housing units where the rent includes meals and other services, such as transportation to shopping and recreation.

Mean Income
Mean income is the amount obtained by dividing the total income of a particular group by the number of individuals or units in that group. For instance, mean household income is obtained by dividing total household income by the total number of households.

Care should be exercised in using and interpreting mean income values for small subgroups of the population. Because the mean is influenced strongly by extreme values in the distribution, it is especially susceptible to the effects of sampling variability, reporting errors, and processing mistakes. The median, which is not affected by extreme values, is a better measure than the mean when the population base is small.

Mean Travel Time to Work
Mean travel time to work is the average travel time in minutes that workers usually took to get from home to work (one-way) during the reference week. This measure is obtained by dividing the total number of minutes taken to get from home to work by the number of workers 16 years old and over who worked outside the home. The travel time includes time spent waiting for public transportation, picking up passengers in carpools, and time spent in other activities related to getting to work.

Means of Transportation to Work (see Commuting to Work)

Median
The median divides a distribution into two equal parts, with one-half of the values greater than the median and one-half less than the median. The median age of a population, for instance, is the age that divides a group in two, with one half of the population older than the median age and one half younger.

Metropolitan/Micropolitan Statistical Areas
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. Current metropolitan and micropolitan statistical area definitions were announced by OMB effective June 6, 2003. The 2000 standards provide that 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. Read more from the Census Bureau.

Mortgage Status
The term mortgage refers to all forms of debt where property is pledged as security for repayment of debt. It includes deeds of trust, trust deeds, contracts to purchase, land contracts, junior mortgages, and home equity loans.

Native (see also Born at Sea & Foreign Born)
The native population includes people born in the United States, Puerto Rico, or the US Island Areas. People who were born in a foreign country but have at least one American parent are also considered to be native.

Nonfamily Household
A nonfamily household consists of a householder living alone or with nonrelatives only.

Noninstitutionalized Population (see Group Quarters Population)

Nonrelative
The Census Bureau classifies household members who are not related to the householder by birth, marriage, or adoption as nonrelatives. Nonrelatives include roomers, boarders, housemates, roommates, unmarried partners, and foster children.

Nursing Homes (see Group Quarters Population)

Occupants per Room
The number of occupants per room is obtained by dividing the number of people in each occupied housing unit by the number of rooms in the unit. Although the Census Bureau has no official definition of crowded units, many users consider units with more than one occupant per room to be crowded.

Occupation
Occupation describes the kind of work a person does on the job. For employed people, the data refer to the person’s job during the reference week. For those who worked at two or more jobs, the data refer to the job at which the person worked the greatest number of hours during the reference week. Some examples of occupational groups include service, sales, and farming. People interested in comparing 1990 and 2000 occupational groups are cautioned that different coding schemes were used in each census. For more information, see: http://www.census.gov/hhes/www/ioindex.html

Occupied Housing Unit
The Census Bureau classifies a housing unit as occupied if it is the usual place of residence of a person or a group of people, or if the occupants are only away temporarily, such as on business or vacation.

Other Relatives
The category "other relatives" includes any household member related to the householder by birth, marriage, or adoption, but not included specifically in another relationship category. Some examples of other relatives include brother-in-law, grandparent, nephew, aunt, cousin, and so forth.

Overseas Population (see Apportionment)

Own Child
The Census Bureau defines an "own child" as a child under 18 years of age who is a son or daughter by birth, marriage (a stepchild), or adoption. For data collected from all respondents (the "100%" data), own children consist of all sons and daughters of householders who are under 18 years of age. For sample data (which are not yet available), own children consist of sons and daughters of householders who are under 18 years of age and who have never been married.

Owner-Occupied Housing Unit
A housing unit is owner-occupied if the owner or co-owner lives in the unit, even if it is mortgaged or not fully paid for.

Per Capita Income
Per capita income is the mean income computed for every person in a particular group. It is calculated by dividing the total income of a particular group by the total population in that group.

Place of Birth (see Born at Sea, Foreign Born, & Native)

PL94-171 (see Redistricting)

Plumbing Facilities
Complete plumbing facilities include (1) hot and cold piped water, (2) a flush toilet, and (3) a bathtub or shower. All three facilities must be located in the housing unit. The Census Bureau obtains data on plumbing facilities from both occupied and vacant housing units.

Population Density (see also Area)
Population density is calculated by dividing the population of a geographic unit by its area, which may be expressed in either square miles, square meters, square kilometers, or any other appropriate unit of measurement. The result is the population per square mile, square meter, and so forth.

Poverty Status in 1999
The Census Bureau measures poverty by using 48 thresholds that vary by family size and the number of children within the family and the age of the householder. In determining poverty status, the bureau compares the total income of a family with the threshold appropriate for that family. If the total family income is less than the threshold, then every member of that family is considered to be poor.

Not every person has a poverty status: institutionalized people, people in military group quarters, people living in college dormitories, and unrelated individuals under 15 years old are considered neither as "poor" nor as "non-poor," and are excluded from both the numerator and the denominator when calculating poverty rates.

The Office of Management and Budget mandates that all federal agencies, including the Census Bureau, use this poverty definition for statistical purposes (OMB Statistical Policy Directive 14, May 1978).

Note: The 48 poverty thresholds are NOT adjusted for differences in the cost of living from one place to another. The poverty thresholds are the same for a household or family living in San Francisco as for one living in rural North Dakota. For more information about poverty, see: http://www.census.gov/hhes/www/poverty.html.

Price Asked
Price asked is the value of vacant housing units that were for sale at the time of the census.

Prisons (see Group Quarters Population)

Quartile
Quartiles divide a distribution into four equal parts. One quarter of the values are below the first quartile, sometimes called the lower quartile. One half of the values are found below the second quartile. Three quarters of the values are below the third, or upper, quartile. Quartiles are presented for certain financial characteristics, such as housing value and contract rent.

Race
The Census Bureau asks everyone to indicate their race; like the question on ethnicity, answers to the question reflect self-identification.

The race question included in the 2000 Census was very different than the question asked in previous censuses. For the first time, respondents could indicate that they belong to more than one racial group, whereas in previous censuses respondents were limited to selecting just one racial group. The 2000 Census products report a total of 63 different race categories, which incorporate every possible combination of the following basic racial designations:

(1) White
(2) Black or African-American
(3) American Indian and Alaska Native
(4) Asian
(5) Native Hawaiian and Other Pacific Islander
(6) Some other race.

Because this is the first time respondents have been allowed to select more than one race category, The racial data in 2000 are not comparable to the racial data in previous censuses. For more information see: http://www.census.gov/population/www/socdemo/race/racefactcb.html.

Real Estate Taxes
Real estate taxes include special assessments, school taxes, county taxes, and any other real estate taxes. Payments on delinquent taxes due from prior years are excluded and any rebates are subtracted from the total. If the taxes are included with the mortgage, a separate amount for real estate taxes is obtained.

Redistricting
Redistricting refers to the process of redrawing federal, state, and local legislative boundaries based on new population counts. In December 1975 Congress passed Public Law 94-171, which specifies that within one year of Census Day, the Census Bureau must send each state the necessary census data to redraw federal, state and local political districts. Redistricting data (sometimes called PL94-171 data) include population counts by race, ethnicity, and the voting age population (18 years of age or older) at all levels of census geography.

This decade, the Census Bureau is required to provide 2000 redistricting data to the 50 states, District of Columbia and Puerto Rico no later than April 1, 2001. For more information, see: http://www.census.gov/clo/www/redistricting.html

Reference Week
The data on employment status and commuting to work are related to a one-week time period, known as the reference week. For each person, this week is the full calendar week, Sunday through Saturday, preceding the date the questionnaire was completed. This calendar week is not the same for all people since the enumeration was not completed in the same week.

Related Children (see Own Children)
Related children include "own children" and all other people under 18 years of age in the household, who are related to the householder. Foster children and the spouse of the householder are not included in this category.

Rent Asked
Rent asked is the monthly amount that a renter is asking for a vacant rental unit at the time of the census.

Rental Vacancy Rate
The rental vacancy rate is the percentage of rental units that are vacant and for rent at any one time. It is calculated by dividing the number of vacant units for rent by the sum of renter-occupied units and vacant units for rent.

Renter-Occupied Housing Unit
The Census Bureau classifies all occupied housing units that are not occupied by their owners, whether they are rented for cash rent or occupied without payment of cash rent, as renter occupied. Housing units in continuing care or life care facilities are considered to be rented for cash rent.

Residence in 1995
Residence in 1995 refers to where a person lived on April 1, 1995.

Resident Parents of Own Children
"Resident Parents of Own Children" refers to parents whose usual residence was the same as that of their own children

Resident Population
The resident population is what the census attempts to enumerate. With the exception of the apportionment data, all census products describe the total or a subgroup of the resident population. The resident population includes:

(1) US citizens living in the US on census day, and
(2) Citizens of foreign countries who have established a household or are part of an established household in the US, or who are living in the United States at embassies, ministries, legations, or consulates.

Note that both legal and illegal immigrants living in the US are included in the resident population.

The resident population does not include:

(1) Members of the US Armed Forces assigned to installations outside the US (and their dependent family members),
(2) US citizens who are working, studying, or living overseas on census day, and
(3) Citizens of foreign countries temporarily traveling or visiting in the US.

For more information on this topic, see: http://www.census.gov/population/www/censusdata/resid_rules.html

Residential Treatment Centers (see Group Quarters Population)

Rooms
The number of rooms in a housing unit is the number of whole rooms used for living purposes. The census collects data for the number of rooms from both occupied and vacant housing units. For each unit, rooms include living rooms, dining rooms, kitchens, bedrooms, finished recreation rooms, enclosed porches suitable for year-round use, and ledger’s rooms. Excluded are strip or Pullman kitchens, bathrooms, open porches, balconies, halls or foyers, half-rooms, utility rooms, unfinished attics or basements, or other unfinished space used for storage. A partially divided room is a separate room only if there is a partition from floor to ceiling, but not if the partition consists solely of shelves or cabinets.

School Enrollment
The Census Bureau classifies individuals as enrolled in school if they reported attending a "regular" public or private school or college at anytime between February 1, 2000 and the time they completed the census. The definition of "regular" schools includes nursery schools, kindergartens, elementary schools, and other schooling that would lead to a high school diploma or college degree. Tutoring or correspondence courses constitute school enrollment if credit can be obtained for this work in a "regular" school. Schools supported and controlled primarily by local, county, state or federal government are defined as public. Those supported and controlled primarily by religious organizations or other private groups are private.

Enrolled persons also report the level in which they are enrolled, from nursery school or preschool through college undergraduate years and graduate and professional school. Vocational, trade, and business schools are not included.

Seasonal, Recreational, or Occasional Use Housing Unit (see Vacancy Status)
Seasonal, recreational, or occasional use housing units include vacant units used or intended for use only in certain seasons, for weekends, for vacations, or other occasional use throughout the year. Interval ownership units, sometimes called shared ownership or time-share condominiums are included in this category.

Selected Monthly Owner Costs
Selected monthly owner costs are the sum of payments for mortgages, deeds of trust, contracts to purchase, or similar debts on the property; real estate taxes; fire, hazard, and flood insurance on the property; utilities; and fuels. It also includes monthly condominium fees or mobile home costs when such fees are paid

Sex
Individuals marked either "male" or "female" to indicate their sex in the census questionnaire.

Shelters (see Group Quarters Population)

Short Form
The short form is the basic census questionnaire, sent to approximately five of six households for the 2000 census. The short form asked population questions about household relationship, sex, race, age and Hispanic or Latino origin, and housing questions related to tenure, occupancy, and vacancy status. All other households received the census long form, which contained all of the questions asked on the short form as well as additional questions about the household and individuals. See long form.

Specified Owner-Occupied Units
Specified owner-occupied units are owner-occupied, one-family, attached and detached houses on less than 10 acres without a business or medical office on the property.

Specified Renter-Occupied Units
Specified renter-occupied units include all renter-occupied units except 1-unit attached or detached houses on 10 acres or more.

Spouse
A spouse is a person who is married to and living with the householder of a home. This category includes people in formal marriages, as well as people in common-law marriages.

Subfamily
When grown children move back to their parent's home with their own children or spouse, they are considered a subfamily.

Specifically, a subfamily consists of either a single parent who lives with at least one child under the age of 18, or a married couple, with or without children. The subfamily lives in the residence of a householder who is related to them, but the householder and spouse are not considered to be part of the subfamily.

Telephone Services
Households with telephone service have a telephone in working order and are able to make and receive calls. The Census Bureau does not consider households whose service has been discontinued for nonpayment or other reasons as having telephone service available.

Tenure
Tenure refers to the distinction between owner-occupied and renter-occupied housing units. A housing unit is owner occupied if the owner or co-owner lives in the unit, even if it is mortgaged or not fully paid for. All occupied housing units that are not owner occupied, whether they are rented for cash rent or occupied without payment of cash rent, are classified as renter occupied.

Unemployed (see also Employed & Labor Force)
The Census Bureau classifies civilians 16 years old and over as unemployed if they (1) were not employed at a job during the reference week, and (2) were looking for work during the last four weeks, and (3) were available to start a job. Also included as unemployed are civilians 16 years old and over who did not work at all during the reference week, or who were waiting to be called back to a job from which they had been laid off, or who were available for work except for temporary illness.

Unmarried Partner (see also Nonrelative)
Within the Census Bureau's classification of household members, an unmarried partner of a relative of the head of household is considered a nonrelative of that household head.

Units in Structure
The Census Bureau publishes data for the number of housing units in structures of various types and sizes. The bureau defines a structure as a separate building that either has open spaces on all sides or is separated from other structures by dividing walls that extend from ground to roof. In determining the number of units in a structure, all housing units, both occupied and vacant, are counted.

Unrelated Individual
An unrelated individual is either a householder living alone or with nonrelatives, or a household member who is not related to the householder, or a person living in group quarters who is not an inmate of an institution.

Urban and Rural Housing
Urban housing comprises all housing units in urbanized areas or urban clusters, but excludes housing units in the rural portions of extended cities.

Housing units not classified as urban are considered to be rural housing.

Urban Area
The Census Bureau classifies densely-populated areas into two groups: urbanized areas and urban clusters.

Urban Cluster
The Census Bureau defines an urban cluster as a densely settled territory that has at least 2,500 people but fewer than 50,000. The bureau introduced this category of urban area for the 2000 census.

Urbanized area
An urbanized area, or UA, consists of a central place and adjacent areas and has a total population of at least 50,000. The urbanized area must also have a minimum population density of 1,000 people per square mile of land area. The Census Bureau uses published criteria to determine the qualification and boundaries of these areas.

Vacancy Status
Census workers classified housing units as either occupied or vacant based on information from residents, landlords, owners, neighbors, and rental agents. They then further subdivided vacant units according to their market status into the following categories:
(1) for rent, (2) for sale only, (3) rented or sold, not occupied, (4) for seasonal, recreational, or occasional use, (5) for migrant workers, and (6) other vacant, which includes units held for occupancy by a caretaker or janitor, and units held for personal reasons by the owner.

Vacant Housing Unit
A housing unit is vacant if no one is living in it at the time of the census (generally, April 1, 2000), unless its occupants are only temporarily absent. Units temporarily occupied at the time of enumeration entirely by people who have a usual residence elsewhere are also classified as vacant

Value
Value is a homeowner's estimate of how much their property (house and lot, mobile home and lot, or condominium unit) would sell for if it were for sale.

Vehicles Available
"Vehicles available" is the number of passenger cards, vans, and pick-up or panel trucks of one-ton capacity or less kept at home and available for use by household members.

Veteran Status
A civilian veteran is a person 18 years old or over who, at the time of the census, had served on active duty in the US Army, Navy, Air Force, Marine Corps, or the Coast Guard in the past (even for a short time), but was not on active duty at the time of the census. Civilian veterans also include those who had served in the Merchant Marine during World War II. People who had served in the National Guard or Military Reserves are classified as veterans only if they had ever been called or ordered to active duty, not counting the 4-6 months for initial training or yearly summer camps.

Workers
The Census Bureau defines "workers 16 years and over" as people over 16 who are either members of the Armed Forces or civilian employees who were at work during the reference week.

Year Householder Moved Into Unit
The "year householder moved into unit" is the year a householder moved into a housing unit. If the householder moved back into a housing unit that he or she previously occupied, then the the year of the latest move is reported.

Year of Entry
The year of entry is the year in which a person born outside the United States came to live in the United States.

Year Structure Built
The census term "year structure built" refers to when a building was first constructed, and not when it was remodeled, added to, or changed in some way.