Census Bureau programs define age as the length of time in completed years that a person has lived. For the most recent decennial census, age was the length of time in completed years that a person had lived as of Census Day--April 1, 2010. The Census Bureau’s national surveys compute age as of the interview date.

The sum of the values for each of the elements in the universe. For example, aggregate household income is the sum of the income of all households in a given geographic area. Aggregates are frequently used in computing mean values (mean equals aggregate divided by universe count).

The amount of time it usually takes workers 16 and over to reach their employment location. Longer travel times can be a result of workers choosing to travel further from home and work, a result of increased congestion on existing roadways, or a combination of the two. Aggregate Travel Time to Work is the sum of the Travel Time to Work for all workers in an area. Mean Travel Time to Work is the Aggregate Travel Time to Work divided by the total number of workers in an area

A statistical area bounded by visible features, such as streets, roads, streams, and railroad tracks, and by nonvisible boundaries, such as selected property lines and city, township, school district, and county limits and short line-of-sight extensions of streets and roads. Generally, blocks are small in area; for example, a city block bounded on all sides by streets. Blocks in suburban and rural areas may be larger, more irregular in shape, and bounded by a variety of features, such as roads, streams, and transmission lines. In remote areas, blocks may even encompass hundreds of square miles. Blocks cover the entire territory of the United States, Puerto Rico, and the Island Areas. Blocks nest within all other tabulated census geographic entities at the time of the decennial census and are the basis for all tabulated data from that census. Census Block Numbers—Blocks are numbered uniquely with a four-digit census block number from 0000 to 9999 within census tract, which nest within state and county. The first digit of the census block number identifies the block group. Block numbers beginning with a zero (in Block Group 0) are intended to include only water area, but not all water-only blocks have block numbers beginning with 0 (zero)

Block Groups are statistical divisions of census tracts, are generally defined to contain between 600 and 3,000 people, and are used to present data and control block numbering. A block group consists of clusters of blocks within the same census tract that have the same first digit of their four-digit census block number. For example, blocks 3001, 3002, 3003, . . . , 3999 in census tract 1210.02 belong to BG 3 in that census tract. Most BGs were delineated by local participants in the Census Bureau’s Participant Statistical Areas Program (PSAP). The Census Bureau delineated BGs only where a local or tribal government declined to participate in PSAP, and a regional organization or the State Data Center was not available to participate. A BG usually covers a contiguous area. Each census tract contains at least one BG, and BGs are uniquely numbered within the census tract. Within the standard census geographic hierarchy, BGs never cross state, county, or census tract boundaries, but may cross the boundaries of any other geographic entity. Tribal census tracts and tribal BGs are separate and unique geographic areas defined within federally recognized American Indian reservations and can cross state and county boundaries (see “Tribal Census Tract” and “Tribal Block Group”). The tribal census tracts and tribal block groups may be completely different from the standard county-based census tracts and block groups defined for the same area.

A number assigned to each census block. Census blocks are numbered uniquely with a four-digit census block number ranging from 0000 to 9999 nesting within each census tract, which nest within state and county. The first digit of the census block number identifies the block group. Block numbers beginning with a zero (in Block Group 0) are associated with water-only areas.

The American Community Survey (ACS) question related to means of transportation asks respondents in the workforce, "How did the person usually get to work LAST WEEK?" Although commutes may involve multiple transportation modes (e.g., driving to a train station and then taking a train), respondents are restricted to indicating the single travel mode used for the longest distance. If the respondent commuted in a car, truck, or van, the number of persons in vehicle is asked to determine whether the commuter drove alone or carpooled.

Daily Vehicle miles traveled (DVMT) is a measure of total vehicle activity for a given time period (usually daily or yearly). It is calculated by multiplying the number of vehicles (traffic volume) on a given roadway segment during a time period by its length. For example, on a 5-mile highway segment traveled by 5,000 vehicles each day the daily VMT is 25,000. The annual DVMT on the same segment is 9,125,000 (25,000 x 365 days).

A long-lasting physical, mental, or emotional condition. This condition can make it difficult for a person to do activities such as walking, climbing stairs, dressing, bathing, learning, or remembering. This condition can also impede a person from being able to go outside the home alone or to work at a job or business.

A measure of commuting into and out of an area. Data reported here include estimates of total daytime population (workers and all other residents). Measures include: Workers who resided and worked in the selected area are residents who do not leave the area for work. Workers who commuted into the selected area are the number of workers commuting into an area. Total workers working in the selected area is the total number of workers working in an area based on their answers to journey- to-work information in the Census. This may include both residents who work in the same area as well as those individuals who commute into the area for work. Workers with residences in the selected area are the total number of workers who live in the selected area minus the total number of workers with residences in the selected area. Estimated daytime population change due to commuting is the total number of workers working in the selected area minus the total number of workers with residences in the selected area. Total resident population is the total number of residents who live in the same area. Estimated daytime population is the total number of residents plus the total number of workers working in the area minus the number of residents who work elsewhere.

Employment status identifies those who:

1. worked at any time during the reference week;
2. were on temporary layoff and available for work;
3. did not work during the reference week but had jobs or businesses from which they were temporarily absent (excluding layoff);
4. did not work during the reference week but were looking for work during the last four weeks and were available to work during the reference week; and
5. were not in the labor force.

A Family, which is the householder and all (one or more) other people living in the same household who are related to the householder by blood, marriage, or adoption. Family Type, refers to how the members of a family are related to one another. Families may be a "Married Couple Family," "Female householder, no spouse present" or "Male householder, no spouse present." A Family Household 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 regarded as members of his or her family. A Family Household may contain people not related to the householder, but those people are not included as part of the householders family in census tabulations. Thus, the number of family households is equal to the number of families, but family households may include more members than do families. 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 Size refers to the number of people in a family.

The Census Bureau classifies all people not living in housing units as living in group quarters. A group quarters is a place where people live or stay, in a group living arrangement, that is owned or managed by an entity or organization providing housing and/or services for the residents. This is not a typical household-type living arrangement. These services may include custodial or medical care as well as other types of assistance, and residency is commonly restricted to those receiving these services. People living in group quarters are usually not related to each other. Group quarters include such places as college residence halls, residential treatment centers, skilled nursing facilities, group homes, military barracks, correctional facilities, and workers’ dormitories.

Includes all people living in group quarters instead of housing units. Group quarters are places where people live or stay, in a group living arrangement, that is owned or managed by an entity or organization providing housing and/or services for the residents. The group quarters population lives in group quarters, of which there are two general categories: Institutional and Non-Institutional Institutional group quarters are facilities that house those who are primarily ineligible, unable, or unlikely to participate in the labor force while resident. The Institutionalized population is the population residing in institutional group quarters such as adult correctional facilities, juvenile facilities, skilled-nursing facilities, and other institutional facilities such as mental (psychiatric) hospitals and in-patient hospice facilities. Non-Institutional group quarters are facilities that house those who are primarily eligible, able, or likely to participate in the labor force while resident. The Non-Institutional population lives in Non-Institutional group quarters such as college/university student housing, military quarters, and other Non-Institutional group quarters such as emergency and transitional shelters for people experiencing homelessness and group homes.

A household includes all the people who occupy a housing unit as their usual place of residence.

These data show the number of passenger cars, vans, and pickup or panel trucks of one-ton capacity or less kept at home and available for the use of household members.

The sum of the income of all people 15 years and older living in the household. A household includes related family members and all the unrelated people, if any, such as lodgers, foster children, wards, or employees who share the housing unit. A person living alone in a housing unit, or a group of unrelated people sharing a housing unit, is also counted as a household.

The total number of people living in a housing unit.

Households are classified by type according to the sex of the householder and the presence of relatives. Examples include: married couple family; male householder, no wife present; female householder, no husband present.

All U.S. residents who live in housing units such as single-family homes, townhouses, apartments, and mobile homes.

The person, or one of the people, in whose name the home is owned, being bought, or rented. If there is no such person present, any household member 15 years old and over can serve as the householder. Two types of householders are distinguished: a family householder and a nonfamily householder. A family householder is a householder living with one or more people related to him or her by birth, marriage, or adoption. The householder and all people in the household related to him are family members. A nonfamily householder is a householder living alone or with nonrelatives only.

A house, an apartment, a mobile home or trailer, a group of rooms, or a single room occupied as separate living quarters, or if vacant, intended for occupancy as separate living quarters. 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. For vacant units, the criteria of separateness and direct access are applied to the intended occupants whenever possible. A housing unit is classified as occupied if it is the usual place of residence of the person or group of people living in it at the time of enumeration.

"Money income" is the income received on a regular basis (exclusive of certain money receipts such as capital gains and lump-sum payments) before payments for personal income taxes, social security, union dues, Medicare deductions, etc. It includes income received from wages, salary, commissions, bonuses, and tips; self-employment income from own nonfarm or farm businesses, including proprietorships and partnerships; interest, dividends, net rental income, royalty income, or income from estates and trusts; Social Security or Railroad Retirement income; Supplemental Security Income (SSI); any cash public assistance or welfare payments from the state or local welfare office; retirement, survivor, or disability benefits; and any other sources of income received regularly such as Veterans (VA) payments, unemployment and/or worker’s compensation, child support, and alimony. The Census Bureau collects income data from several surveys. Depending on your needs, one survey may be more suitable than another. The following is a list of Census Bureau surveys:

• Annual Social and Economic Supplement to the Current Population Survey (CPS ASEC)
• American Community Survey (ACS)
• Survey of Income and Program Participation (SIPP)
• Census 2000 long form
• Small Area Income and Poverty Estimates program (SAIPE)

Each of these surveys differs from the others in some ways, such as the length and detail of its questionnaire, the number of households included (sample size), and the methodology used to collect and process the data. The Small Area Income and Poverty Estimates program uses statistical models to produce income and poverty estimates by combining survey results with administrative records. Per capita income is the mean income computed for every man, woman, and child in a particular group. It is derived by dividing the total income of a particular group by the total population. Mean Household Income is the total household income for the area divided by the number of households.

Industry (population data): Information on industry relates to the kind of business conducted by a person’s employing organization. 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. Some examples of industrial groups shown in products include agriculture, forestry, and fisheries; construction; manufacturing; wholesale or retail trade; transportation and communication; personal, professional and entertainment services; and public administration. Industry (economic): U.S. industries are classified using a 5- or 6-digit NAICS code. Industry groups are represented by classification using a 4-digit NAICS code. For further information on the NAICS please see North American Industry Classification System (NAICS).

The labor force includes all people classified in the civilian labor force, plus members of the U.S. Armed Forces (people on active duty with the United States Army, Air Force, Navy, Marine Corps, or Coast Guard). The Civilian Labor Force consists of people classified as employed or unemployed. Employed includes all civilians 16 years old and over who were either:

1. "at work" -- those who did any work at all 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; or
2. were "with a job but not at work" -- those who did not work during the reference week but had jobs or businesses from which they were temporarily absent due to illness, bad weather, industrial dispute, vacation, or other personal reasons.

Excluded from the employed are people whose only activity consisted of work around the house or unpaid volunteer work for religious, charitable, and similar organizations; also excluded are people on active duty in the United States Armed Forces. The reference week is the calendar week preceding the date on which the respondents completed their questionnaires or were interviewed. This week may not be the same for all respondents.

Employment status identifies those who:

1. worked at any time during the reference week;
2. were on temporary layoff and available for work;
3. did not work during the reference week but had jobs or businesses from which they were temporarily absent (excluding layoff);
4. did not work during the reference week but were looking for work during the last four weeks and were available to work during the reference week; and
5. were not in the labor force.

The language spoken at home for people age 5 and older. The language currently used by respondents at home, either "English only" or a non-English language which is used in addition to English or in place of English. The Census Bureau asks individuals if they speak a language other than English at home. Respondents are asked to provide the language spoken. In addition, those individuals that indicate that they speak a language other than English at home were asked how well they spoke English (ranked from "not at all" to "very well").

Term used in Census 2000 data products to identify a household in which all members 14 years old and over speak a non-English language and also speak English less than ‘‘very well.’’ In a linguistically isolated household, no one 14 years old or older speaks only English. All the members of a linguistically isolated household are tabulated as linguistically isolated, including members under 14 years old who may speak only English. The term "linguistic isolation or "Linguistically Isolated Households" is also referred to as Households with Limited English Speaking Status. Households with Limited English Speaking Status is the updated term. The Census Bureau still tabulates statistics for these households but no longer uses the terms "linguistic isolation."

Mean income is the amount obtained by dividing the total income of a particular statistical universe by the number of units in that universe. Thus, mean household income is obtained by dividing total household income by the total number of households. For the various types of income, the means are based on households having those types of income.

The principal mode of travel or type of conveyance, by distance rather than time, that the worker usually used to get from home to work during the employment status reference week.

A geographic entity delineated by the Office of Management (OMB) and Budget for use by federal statistical agencies. Metropolitan statistical areas consist of the county or counties (or equivalent entities) associated with at least one urbanized area of at least 50,000 population, plus adjacent counties having a high degree of social and economic integration with the core as measured through commuting ties. Micropolitan (as opposed to Metropolitan) statistical areas consist of the county or counties (or equivalent entities) associated with at least one urban cluster of at least 10,000 but less than 50,000 population, plus adjacent counties having a high degree of social and economic integration with the core as measured through commuting ties. Metropolitan and micropolitan statistical areas are collectively referred to as "Core Based Statistical Areas" (CBSAs).

The Census Bureau classifies all people not living in housing units as living in group quarters. A group quarters is a place where people live or stay, in a group living arrangement, that is owned or managed by an entity or organization providing housing and/or services for the residents. This is not a typical household-type living arrangement. These services may include custodial or medical care as well as other types of assistance, and residency is commonly restricted to those receiving these services. People living in group quarters are usually not related to each other. Group quarters include such places as college residence halls, residential treatment centers, skilled nursing facilities, group homes, military barracks, correctional facilities, and workers’ dormitories.

The North American Industry Classification System (NAICS, pronounced Nakes) was developed under the direction and guidance of the Office of Management and Budget (OMB) as the standard for use by Federal statistical agencies in classifying business establishments for the collection, tabulation, presentation, and analysis of statistical data describing the U.S. economy. Use of the standard provides uniformity and comparability in the presentation of these statistical data. NAICS is based on a production-oriented concept, meaning that it groups establishments into industries according to similarity in the processes used to produce goods or services. NAICS replaced the Standard Industrial Classification (SIC) system in 1997.

NAICS is a 2- through 6-digit hierarchical classification system, offering five levels of detail. Each digit in the code is part of a series of progressively narrower categories, and the more digits in the code signify greater classification detail. The first two digits designate the economic sector, the third digit designates the subsector, the fourth digit designates the industry group, the fifth digit designates the NAICS industry, and the sixth digit designates the national industry. The 5-digit NAICS code is the level at which there is comparability in code and definitions for most of the NAICS sectors across the three countries participating in NAICS (the United States, Canada, and Mexico). The 6-digit level allows for the United States, Canada, and Mexico each to have country-specific detail. A complete and valid NAICS code contains six digits.

For more information, see the NAICS website.

Occupation describes the kind of work the 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. Some examples of occupational groups shown in this product include managerial occupations; business and financial specialists; scientists and technicians; entertainment; healthcare; food service; personal services; sales; office and administrative support; farming; maintenance and repair; and production workers.

Per capita income is the mean income computed for every man, woman, and child in a particular group. It is derived by dividing the total income of a particular group by the total population.

The difference between the population of an area at the beginning and end of a time period, expressed as a percentage of the beginning population. Percent population change is computed by subtracting the number of people at an earlier period of time from the population at a later period of time, then dividing the difference by the population at the earlier period and multiplying the result by 100.

Estimates of the population for future dates. They illustrate plausible courses of future population change based on assumptions about future births, deaths, international migration, and domestic migration. Projections are based on an estimated population consistent with the most recent decennial census as enumerated. While projections and estimates may appear similar, there are some distinct differences between the two measures. Estimates usually are for the past, while projections typically are for future dates. Estimates generally use existing data, while projections must assume what demographic trends will be in the future. For dates when both population estimates and projections are available, population estimates are the preferred data. The source of the Texas population projections reported here are from the Texas Demographic Center at the University of Texas at San Antonio (UTSA).

Equivalent to average household size which is a measure obtained by dividing the number of people in households by the total number of households (or householders).

All people, male and female, child and adult, living in a given geographic area.

The number of people per square mile.

The calculated number of people living in an area as of a specified point in time, usually July 1st. The estimated population is calculated using a component of change model that incorporates information on natural increase (births, deaths) and net migration (net domestic migration, net international migration) that has occurred in an area since the latest decennial census. The source of the Texas population estimates reported here are from the Texas Demographic Center at UTSA.

Includes all people living in group quarters instead of housing units. Group quarters are places where people live or stay, in a group living arrangement, that is owned or managed by an entity or organization providing housing and/or services for the residents. The group quarters population lives in group quarters, of which there are two general categories: Institutional and Non-Institutional Institutional group quarters are facilities that house those who are primarily ineligible, unable, or unlikely to participate in the labor force while resident. The Institutionalized population is the population residing in institutional group quarters such as adult correctional facilities, juvenile facilities, skilled-nursing facilities, and other institutional facilities such as mental (psychiatric) hospitals and in-patient hospice facilities. Non-Institutional group quarters are facilities that house those who are primarily eligible, able, or likely to participate in the labor force while resident. The Non-Institutional population lives in Non-Institutional group quarters such as college/university student housing, military quarters, and other Non-Institutional group quarters such as emergency and transitional shelters for people experiencing homelessness and group homes.

Following the OMB’s Directive 14, the Census Bureau uses a set of money income thresholds that vary by family size and composition to determine who is in poverty. If the total income for a family or unrelated individual falls below the relevant poverty threshold, then the family (and every individual in it) or unrelated individual is considered in poverty.

Ethnicity: The U.S. Census Bureau adheres to the OMB definition of ethnicity. There are two minimum categories for ethnicity: Hispanic or Latino and Not Hispanic or Latino. OMB considers race and Hispanic origin to be two separate and distinct concepts. Hispanics and Latinos may be of any race. Race: The data on race were derived from answers to the question on race. The U.S. Census Bureau collects race data in accordance with guidelines provided by the OMB, and these data are based on self-identification. The racial categories included in the census questionnaire generally reflect a social definition of race recognized in this country and not an attempt to define race biologically, anthropologically, or genetically. In addition, it is recognized that the categories of the race question include race and national origin or sociocultural groups. OMB requires that race data be collected for a minimum of five groups: White, Black or African American, American Indian or Alaska Native, Asian, and Native Hawaiian or other Pacific Islander. OMB permits the Census Bureau to also use a sixth category - Some Other Race. Respondents may report more than one race.

The number of vehicles registered in a particular county. The data do not distinguish between commercial and non-commercial vehicles.

Enrollment refers to being registered or listed as a student in an educational program leading to a high school diploma or college degree. This may be a public school or college, a private school or college, or home school. In some surveys, the Census Bureau also asks about school "attendance," which is treated as equivalent to enrollment.

For the purpose of Census Bureau surveys and the decennial census, sex refers to a person’s biological sex. Distinction between the concepts of gender and sex In general discussions, the concept of gender is often confused with the concept of sex, and the terms are used interchangeably. The meanings of these two concepts are not the same: sex is based on the biological attributes of men and women (chromosomes, anatomy, hormones), while gender is a social construction whereby a society or culture assigns certain tendencies or behaviors the labels of masculine or feminine. These assignments may differ across cultures and among people within a culture, and even across time. Gender may or may not correspond directly to sex--depending on the society or culture or period. That means, for example, that people may associate themselves with femininity (as defined by their culture) while being biologically male. At the Census Bureau, the sex question wording very specifically intends to capture a person's biological sex and not gender. Ambiguity of these two concepts interferes with accurately and consistently measuring what we intend to measure--the sex composition of the population.

A unit of measurent equal to the area of a square which is one mile in length on each side. Often times, raw data released by the Census Bureau, representing the size of a geographical area, i.e. county, is given in square meters which then need be converted to square miles for reporting purposes. Square miles are calculated by dividing the square meters by 2,589,988.

Two measures of highway infrastructure include centerline miles and lane miles. Centerline miles is the length of the roadway measured in miles. Lane miles is the number of lanes times the length of the roadway.

Data files available from Census 2000 and the 2010 Census. This file presents 100-percent population and housing figures for the total population, for 63 race categories, and for many other race and Hispanic or Latino categories. This includes age, sex, households, household relationship, housing units, occupancy status, and tenure (whether the residence is owned or rented). Also included are selected characteristics for a limited number of race and Hispanic or Latino categories. The data are available for the U.S., regions, divisions, states, counties, county subdivisions, places, census tracts, block groups, blocks, metropolitan areas (2000), core based statistical areas (2010), American Indian and Alaska Native areas, tribal subdivisions, Hawaiian home lands, congressional districts, and ZIP Code Tabulation Areas. Data are available down to the block level for many tabulations, but only to the census-tract level for others. The 2010 Census SF1 has some tables on the population in group quarters that are available only to the county level. The Census 2000 Summary File 1 data were released in three stages. Individual state files and two national files were released. The state-level data were released first, followed by the Advance National File, which covered the same data subjects, but includes national level summary data for areas that cross state boundaries such as whole metropolitan areas, whole American Indian areas, etc. The Final National File contains the same data subjects and geographic areas as the Advance National File, but adds the first available urban/rural and urbanized area data. The 2010 Census Summary File 1 data were released in stages. Individual state files and a national update were released in 2011. The SF1 urban/rural update was released in Fall 2012. This file contains the same data subjects as the previously released files, but for additional geography, including the urban and rural parts of the United States, regions, divisions, states, counties, and places; and urbanized areas and urban clusters.

Data files produced from the 2010 and 2000 census. Summary File 2 presents data similar to the information included in Summary File 1. For the 2010 Census, the data are shown down to the census tract level for up to 331 race, Hispanic or Latino, and American Indian and Alaska Native groups. For Census 2000, these data are shown down to the census tract level for up to 250 race, Hispanic or Latino, and American Indian and Alaska Native tribe categories. For data to be shown in SF 2, a population category must meet a population size threshold of 100 or more people of that specific population category in a specific geographic area.

This Census 2000 file presents data on the population and housing long form subjects such as income and education. It includes population totals for ancestry groups. It also includes selected characteristics for a limited number of race and Hispanic or Latino categories. The data are available for the U.S., regions, divisions, states, counties, county subdivisions, places, census tracts, block groups, metropolitan areas, American Indian and Alaska Native areas, tribal subdivisions, Hawaiian home lands, congressional districts, and Zip Code Tabulation Areas. After Census 2000, data on these subjects were produced from the ACS or the Puerto Rico Community Survey.

This Census 2000 file presents data similar to the information included in Summary File 3. These data are shown down to the census tract level for up to 336 race, Hispanic or Latino, American Indian and Alaska Native tribe, and ancestry categories. For data to be shown in SF 4, there must be at least 50 unweighted sample cases of a specific population category in a specific geographic area. In addition, the data for the specific population category for the specific geographic area must also have been available in Summary File 2. After Census 2000, data on these subjects were produced from the ACS Survey or the Puerto Rico Community Survey.

This housing characteristic is asked on the Census questionnaire for all occupied housing units in order to classify the unit as "Owner occupied" or "Renter occupied." Tenure data have been collected by the Census Bureau since 1890, though with different details regarding ownership (with or without a mortgage) and rent (with or without cash payment). Owner occupied housing units are those in which the person completing the questionnaire or someone else who lives in the household owns the housing unit, even if it is mortgaged or in the process of being purchased. Renter occupied housing units are not occupied by the owner and are classified as "Renter occupied" if someone other than the owner occupies the unit whether the unit is rented or occupied without cash rent. A housing unit is classified as occupied if it is the usual place of residence of the person or group of people living in it at the time of enumeration.

The amount of time it usually takes workers 16 and over to reach their employment location. Longer travel times can be a result of workers choosing to travel further from home and work, a result of increased congestion on existing roadways, or a combination of the two. Aggregate Travel Time to Work is the sum of the Travel Time to Work for all workers in an area. Mean Travel Time to Work is the Aggregate Travel Time to Work divided by the total number of workers in an area.

All civilians 16 years old and over are classified as unemployed if they

1. were neither "at work" nor "with a job but not at work" during the reference week, and
2. were actively looking for work during the last 4 weeks, and (3) were available to accept a job.

Also included as unemployed are civilians who did not work at all during the reference week, were waiting to be called back to a job from which they had been laid off, and were available for work except for temporary illness.

Represents the number of unemployed people as a percentage of the civilian labor force.

The principal mode of travel or type of conveyance, by distance rather than time, that the worker usually used to get from home to work during the employment status reference week.

These data show the number of passenger cars, vans, and pickup or panel trucks of one-ton capacity or less kept at home and available for the use of household members.

Daily Vehicle miles traveled (DVMT) is a measure of total vehicle activity for a given time period (usually daily or yearly). It is calculated by multiplying the number of vehicles (traffic volume) on a given roadway segment during a time period by its length. For example, on a 5-mile highway segment traveled by 5,000 vehicles each day the daily VMT is 25,000. The annual DVMT on the same segment is 9,125,000 (25,000 x 365 days).

The ACS includes a question on means of transportation to work asked of those ages 16 and over who were employed and at work in the previous week. Individuals working at home are those who reported ‘‘work at home’’ on this question.

Workers: This term appears in connection with several subjects: journey-to-work items, class of worker, work status in the past 12 months, weeks worked in the past 12 months, and number of workers in family in the past 12 months. Its meaning varies and, therefore, should be determined in each case by referring to the definition of the subject in which it appears.

Class of Worker:

All people over the age of 15 who have been employed at any time are asked to designate the type of work normally done or the work performed most regularly. Occupations and types of work are then broken down into the following 5 classes:

• Private Wage and Salary Workers -- Includes people who worked for wages, salary, commission, tips, pay-in-kind, or piece rates for a private-for-profit employer or a private-not-for-profit, tax-exempt, or charitable organization. Self-employed people whose business was incorporated are included with private wage and salary workers because they are paid employees of their own companies. Some tabulations present data separately for these subcategories: "For profit," "Not-for-profit," and "Own business incorporated."
• Government Workers -- Includes people who are employees of any local, state, or federal governmental unit, regardless of the activity of the particular agency. For some tabulations, the data are presented separately for the three levels of government. Employees of foreign governments, the United Nations, or other formal international organizations controlled by governments should be classified as "Federal Government employee."
• Self-Employed Workers -- Includes people who worked for profit or fees in their own unincorporated business, profession, or trade, or who operated a farm.
• Unpaid Family Workers -- Includes people who worked 15 hours or more without pay in a business or on a farm operated by a relative.
• Salaried/Self-Employed -- In tabulations that categorize persons as either salaried or self-employed, the salaried category includes private and government wage and salary workers; self-employed includes self-employed people and unpaid family workers

The labor force includes all people classified in the civilian labor force, plus members of the U.S. Armed Forces (people on active duty with the United States Army, Air Force, Navy, Marine Corps, or Coast Guard). The Civilian Labor Force consists of people classified as employed or unemployed. Employed includes all civilians 16 years old and over who were either:

1. "at work" -- those who did any work at all 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; or
2. were "with a job but not at work" -- those who did not work during the reference week but had jobs or businesses from which they were temporarily absent due to illness, bad weather, industrial dispute, vacation, or other personal reasons.

Excluded from the employed are people whose only activity consisted of work around the house or unpaid volunteer work for religious, charitable, and similar organizations; also excluded are people on active duty in the United States Armed Forces. The reference week is the calendar week preceding the date on which the respondents completed their questionnaires or were interviewed. This week may not be the same for all respondents.