GIS in Prevention, County Profiles, Series 3 (2006) A. Census Definitions The following is an excellent source of definitions and explanations of geography-related terms used by the U.S. Census 2000: Block Group (BG) A statistic subdivision of a census tract. Includes all blocks whose numbers begin with the same digit in a census tract. For example, for Census 2000, BG3 within a census tract includes all blocks numbered from 3000 to BGs generally contain between 300 and 3000 persons, with an optimal size of 1,500 people. Census Tract (CT) A small, relatively permanent statistical subdivision of a county or statistically equivalent entity. Designed to be relatively homogeneous units with respect to population characteristics, economic status, and living conditions at the time they are established. CTs generally contain between 1,000 and 8,000 persons, with an optimal size of 4,000 people. CT numbers range from 001 to Rural All territory, population, and housing units located outside of urbanized areas and urban clusters. Urban All territory, population, and housing units located within urbanized areas and urban clusters. Urban area. A generic term that refers to both urbanized areas and urban clusters. This terminology is new for Census Urban cluster (UC) A densely settled area that has a census population of 2,500 to 49,999. A UC generally consists of a geographic core of block groups or blocks that have a population density of at least 1,000 people per square mile, and adjacent block groups and blocks with at least 500 people per square mile. Urbanized area (UA) A densely settled area that has a census population of at least 50,000. A UA generally consists of a geographic core of block groups or blocks that have a population density of at least 1,000 people per square mile, and adjacent block groups and blocks with at least 500 people per square mile. A UA consists of all or part of one or more incorporated places and/or census designated places, and may include additional territory outside of any place.

GIS in Prevention, County Profiles, Series 3 (2006) A. Census Definitions, cont. The following is an excellent source of definitions and explanations of social, economic and housing characteristics and general terms used by the U.S. Census 2000: Labor Force. All people classified in the civilian labor force (i.e., employed and unemployed people), plus members of the U.S. Armed Forces (on active duty). Group Quarters. Includes all people not living in households. Includes institutionalized population and non-institutionalized population (such as college dormitories, military quarters, and group homes, and the staff residing at these quarters. Household. A household includes all of the people who occupy a housing unit. A housing unit is a house, an apartment, a mobile home, a group of rooms, or a single room occupied as separate living quarters. The occupants may be a single family, one person living alone, two or more families living together, or an other group of related or unrelated people who share living quarters. Spouse (husband/wife) A person married to and living with a householder. People in formal marriages, as well as people in common law marriages, are included. Child. A son or daughter by birth, a stepchild, or an adopted child of the householder, regardless of the child’s age or marital status. The category excludes sons-in-law, daughters-in-law, and foster children. Own child. A never-married child under 18 who is son or daughter of the householder by birth, marriage (a stepchild), or adoption.

GIS in Prevention, County Profiles, Series 3 (2006) A. Census Definitions, cont. Family Type. A family includes a householder and one or more other people living in the same household who are related to the householder by birth, marriage, or adoption. Not all households contain families, since a household may be comprised of a group of unrelated people or of one person living alone. Income of households. This 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. Income of families. The incomes of all members 15 years old and over related to the householder are summed and treated as a single amount. Median income. The median divides the income distribution into two equal parts: one half of the cases falling below the median income and one-half above the median. Per capita income. The mean income computed for every man, woman, and child in a particular group (dividing the total income of a particular group by the total population in that group). Industry. The classification system consists of 265 categories for employed people, classified into 14 major industry groups (developed from the 1997 North American Industry Classification System, NAICS). Occupation. Consists of 509 specific occupational categories for employed people arranged into 23 major occupational groups (developed based on the Standard Occupational Classification, SOC, Manual: 2000). Appendix A, cont.

GIS in Prevention, County Profiles, Series 3 (2006) A. Census Definitions, cont. Poverty Status. The Census Bureau uses the federal government’s official poverty definition. The Social Security Administration developed the original poverty definition in 1964, revised in 1969 and Since the UDSA’s 1955 Food Consumption Survey showed that families of three or more people across all income levels spent roughly one-third of their income on food, the SSA multiplied the cost of the Economy Food Plan by three to obtain dollar figures for the poverty thresholds. Poverty thresholds vary by family size and composition. Poverty thresholds are revised annually to allow for changes in the cost of living as reflected in the Consumer Price Index. The poverty thresholds are the same for all parts of the country – they are not adjusted for regional, state, or local variations in the cost of living. The weighted average threshold for 3-person families was $13,032 for three adults; $13,410 for 2 adults and a child; and $13,423 for 2 children and 1 adult. Individuals for whom poverty status is determined. All people except institutionalized people, people in military group quarters, people in college dormitories, and unrelated individuals under 15 years old. They are considered neither “poor” nor “nonpoor.” Household poverty data. Poverty status is not defined for households --- only for families and unrelated individuals. Race. The concept of race, as used by the Census Bureau, reflects self-identification by people according to the race or races with which they most closely identify. These categories are socio-political constructs and should not be interpreted as being scientific or anthropological in nature. Furthermore, the race categories include both racial and national-origin groups. Vehicles available. Show the number of passenger cars, vans, and pickup or panel trucks of 1-ton capacity or less kept at home and available for the use of household members. Appendix A, cont.