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  1. Title: Census Counties, 2000 - San Francisco Bay Area, California

    Contributors:

    Summary: This polygon shapefile displays the 9 counties for the San Francisco Bay Area of California, as of January 1, 2000. The primary legal divisions of most states are termed ''counties.'' Each county and statistically equivalent entity is assigned a three-digit Federal Information Processing Standards code that is unique within the state. These codes are assigned in alphabetical order of county or county equivalent within each state.This layer is part of the Bay Area Metropolitan Transportation Commission (MTC) GIS Maps and Data collection. This dataset is intended for researchers, students, and policy makers for reference and mapping purposes, and may be used for basic applications such as viewing, querying, and map output production, or to provide a basemap to support graphical overlays and analysis with other spatial data. California, Metropolitan Transportation Commission. (2002). Census Counties, 2000 - San Francisco Bay Area, California. MTC. Available at: http://purl.stanford.edu/hv237bh9962. This layer is presented in the WGS84 coordinate system for web display purposes. Downloadable data are provided in native coordinate system or projection.

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  2. Title: Census Blocks, 2000 - San Francisco Bay Area, California

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    Summary: This polygon shapefile represents U.S. Census Blocks for the San Francisco Bay Area of California as of the year 2000. Census blocks are statistical areas bounded on all sides by visible features such as streets, roads, streams, and railroad tracks, and by invisible boundaries such as city, town, township, and county limits, and short imaginary extensions of streets and roads. Generally census blocks are small in area; for example, a block in a city bounded by streets. However, census blocks in remote areas may be large and irregular and contain hundreds of square miles. All territory in the United States, Puerto Rico, and the Island Areas have block numbers. Blocks are composed of one or more GT-polygons; that is, several GT-polygons can share the same block number. Census 2000 Block Numbers. Census 2000 tabulation blocks are numbered uniquely within each state/county/census tract with a four-digit census block number. The U.S. Census Bureau created the tabulation block numbers immediately before beginning its Census 2000 data tabulation process, thereby eliminating block suffixes. The first digit of the tabulation block number identifies the block group. For the 1990 census, the U.S. Census Bureau assigned a unique 1990 block number with a suffix of "Z" to identify crews-of-vessels population. For Census 2000, crews-of-vessels population is assigned to the land block identified by the U.S. Census Bureau as associated with the home port of the vessel. Water Blocks. The U.S. Census Bureau introduced a different method for identifying the water areas of census blocks for Census 2000. For the 1990 census, water was not uniquely identified within a census block; instead, all water area internal to a block group was given a single block number ending in "99" (for example, in block group 1, all water was identified as block 199). A suffix was added to each 1990 water block number where the block existed in more than one tabulation entity within its block group. For Census 2000, water area located completely within the boundary of a single land block has the same block number as that land block. Water area that touches more than one land block is assigned a unique block number not associated with any adjacent land block. The U.S. Census Bureau assigned water block numbers beginning with the block group number followed by "999 " and preceding in descending order. For example, in block group 3, the block numbers assigned to water areas that border multiple land blocks are 3999, 3998, 3997, and so forth. Because some land blocks include water (ponds and small lakes), no conclusions about whether or not a block is all land or all water can be made by looking at the Census 2000 block numbers. Data users must use the WATER field on Record Type S to determine if the GT-polygon is land or water. The WATER field has two values, 0 for land or 1 for water. This layer is part of the Bay Area Metropolitan Transportation Commission (MTC) GIS Maps and Data collection This dataset is intended for researchers, students, and policy makers for reference and mapping purposes, and may be used for basic applications such as viewing, querying, and map output production, or to provide a basemap to support graphical overlays and analysis with other spatial data. California, Metropolitan Transportation Commission. (2002). Census Blocks, 2000 - San Francisco Bay Area, California. MTC. Available at: http://purl.stanford.edu/rv407ym2175. This layer is presented in the WGS84 coordinate system for web display purposes. Downloadable data are provided in native coordinate system or projection.

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  3. Title: 2000 Census Traffic Analysis Zones - San Francisco Bay Area, California

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    Summary: This polygon shapefile contains the traffic analysis zones (TAZs) for the San Francisco Bay Area in California. These data have been clipped to the shoreline for cartographic representation. TAZs are special-purpose geographic entities delineated by state and local transportation officials for tabulating traffic related data from the decennial census, especially journey-to-work and place-of-work statistics. A TAZ usually consists of one or more census blocks, block groups, or census tracts. Each TAZ is identified by a 6-character alphanumeric census code that is unique within county or statistically equivalent entity. A code of ZZZZZZ indicates a portion of a county where no TAZs were defined. This layer is part of the Bay Area Metropolitan Transportation Commission (MTC) GIS Maps and Data collection. This dataset is intended for researchers, students, and policy makers for reference and mapping purposes, and may be used for basic applications such as viewing, querying, and map output production, or to provide a basemap to support graphical overlays and analysis with other spatial data. California, Metropolitan Transportation Commission. (2002). 2000 Census Traffic Analysis Zones - San Francisco Bay Area, California. MTC. Available at: http://purl.stanford.edu/tm960wp6354. This layer is presented in the WGS84 coordinate system for web display purposes. Downloadable data are provided in native coordinate system or projection.

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  4. Title: Census Blocks, 2000 - San Francisco Bay Area, California

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    Summary: The polygons in this data layer represent U.S. Census Blocks for the San Francisco Bay Area in California. These data have been clipped to the shoreline for cartographic representation. Census blocks are statistical areas bounded on all sides by visible features such as streets, roads, streams, and railroad tracks, and by invisible boundaries such as city, town, township, and county limits, and short imaginary extensions of streets and roads. Generally census blocks are small in area; for example, a block in a city bounded by streets. However, census blocks in remote areas may be large and irregular and contain hundreds of square miles. All territory in the United States, Puerto Rico, and the Island Areas have block numbers. Blocks are composed of one or more GT-polygons; that is, several GT-polygons can share the same block number. Census 2000 Block Numbers. Census 2000 tabulation blocks are numbered uniquely within each state/county/census tract with a four-digit census block number. The U.S. Census Bureau created the tabulation block numbers immediately before beginning its Census 2000 data tabulation process, thereby eliminating block suffixes. The first digit of the tabulation block number identifies the block group. For the 1990 census, the U.S. Census Bureau assigned a unique 1990 block number with a suffix of "Z" to identify crews-of-vessels population. For Census 2000, crews-of-vessels population is assigned to the land block identified by the U.S. Census Bureau as associated with the home port of the vessel. Water Blocks. The U.S. Census Bureau introduced a different method for identifying the water areas of census blocks for Census 2000. For the 1990 census, water was not uniquely identified within a census block; instead, all water area internal to a block group was given a single block number ending in "99" (for example, in block group 1, all water was identified as block 199). A suffix was added to each 1990 water block number where the block existed in more than one tabulation entity within its block group. For Census 2000, water area located completely within the boundary of a single land block has the same block number as that land block. Water area that touches more than one land block is assigned a unique block number not associated with any adjacent land block. The U.S. Census Bureau assigned water block numbers beginning with the block group number followed by "999 " and preceding in descending order. For example, in block group 3, the block numbers assigned to water areas that border multiple land blocks are 3999, 3998, 3997, and so forth. Because some land blocks include water (ponds and small lakes), no conclusions about whether or not a block is all land or all water can be made by looking at the Census 2000 block numbers. Data users must use the WATER field on Record Type S to determine if the GT-polygon is land or water. The WATER field has two values, 0 for land or 1 for water. This layer is part of the Bay Area Metropolitan Transportation Commission (MTC) GIS Maps and Data collection. This dataset is intended for researchers, students, and policy makers for reference and mapping purposes, and may be used for basic applications such as viewing, querying, and map output production, or to provide a basemap to support graphical overlays and analysis with other spatial data. California, Metropolitan Transportation Commission. (2002). Census Blocks, 2000 - San Francisco Bay Area, California. MTC. Available at: http://purl.stanford.edu/ts501wk9853. This layer is presented in the WGS84 coordinate system for web display purposes. Downloadable data are provided in native coordinate system or projection.

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  5. Title: Census Landmark Polygon Features, 2000 - San Francisco Bay Area, California

    Contributors:

    Summary: This polygon shapefile displays landmark features throughout the San Francisco Bay Area in California. "Landmark" is the general name given to a cartographic (or locational) landmark, a land-use area, and a key geographic location (KGL). A cartographic landmark is identified for use by an enumerator while working in the field. A land-use area is identified in order to minimize enumeration efforts in uninhabited areas or areas where human access is restricted. A key geographic location is identified in order to more accurately geocode and enumerate a place of work or residence. The predominant feature classes represented in this layer include airports or airfields, cemeteries, fraternities or sororities, state or local parks or forests, golf courses, lookout towers, educational and religious institutions. Other possible landmark features could include military installations, multi-household or transient quarters, custodial facilities, other types of transportation facilities or terminals, employment centers, open space and other special landmark designations for post offices, police stations and firehouses. The Census Bureau includes landmarks in the Census TIGER data base for locating special features and to help enumerators during field operations. The Census Bureau added landmark features on an as-needed-basis and made no attempt to ensure that all instances of a particular feature were included. The absence of a landmark does not mean that the living quarters, e.g., hospitals and group quarters associated with the landmark were excluded from the 1990 enumeration. A census feature class code (CFCC) is used to identify the most noticeable characteristic of a feature. The CFCC is applied only once to a chain or landmark with preference given to classifications that cover features that are visible to an observer and a part of the ground transportation network. Thus, a road that also is the boundary of a town would have a CFCC describing its road characteristics, not its boundary characteristics. The CFCC, as used in the TIGER/Line files, is a three-character code. The first character is a letter describing the feature class; the second character is a number describing the major category; and the third character is a number describing the minor category. Landmark (Feature Class D) is the general name given to a cartographic (or locational) landmark, a land-use area, and a key geographic location. This layer is part of the Bay Area Metropolitan Transportation Commission (MTC) GIS Maps and Data collection. This dataset is intended for researchers, students, and policy makers for reference and mapping purposes, and may be used for basic applications such as viewing, querying, and map output production, or to provide a basemap to support graphical overlays and analysis with other spatial data. California, Metropolitan Transportation Commission. (2002). Census Landmark Polygon Features, 2000 - San Francisco Bay Area, California. MTC. Available at: http://purl.stanford.edu/mw173fz6932. This layer is presented in the WGS84 coordinate system for web display purposes. Downloadable data are provided in native coordinate system or projection.

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  6. Title: Census Counties, 2000 - San Francisco Bay Area, California (Clipped)

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    Summary: This polygon shapefile displays the boundaries for the 9 counties of the San Francisco Bay Area in California as of January 1, 2000. These data have been clipped to the shoreline for cartographic representation. The primary legal divisions of most states are termed ''counties.'' Each county and statistically equivalent entity is assigned a three-digit Federal Information Processing Standards (FIPS) code that is unique within the state. These codes are assigned in alphabetical order of county or county equivalent within each state. This layer is part of the Bay Area Metropolitan Transportation Commission (MTC) GIS Maps and Data collection. This dataset is intended for researchers, students, and policy makers for reference and mapping purposes, and may be used for basic applications such as viewing, querying, and map output production, or to provide a basemap to support graphical overlays and analysis with other spatial data. California, Metropolitan Transportation Commission. (2002). Census Counties, 2000 - San Francisco Bay Area, California (Clipped). MTC. Available at: http://purl.stanford.edu/xv509rh6426. This layer is presented in the WGS84 coordinate system for web display purposes. Downloadable data are provided in native coordinate system or projection.

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  7. Title: Census Places, 1990 - San Francisco Bay Area, California (Clipped)

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    Summary: This polygon shapefile contains the Census places for the San Francisco Bay Area based as of January 1, 2000. These data have been clipped to the shoreline for cartographic representation. Places, for the reporting of decennial census data, include census designated places, consolidated cities, and incorporated places. Each place is assigned a five-digit Federal Information Processing Standards (FIPS) code. This layer is part of the Bay Area Metropolitan Transportation Commission (MTC) GIS Maps and Data collection. This dataset is intended for researchers, students, and policy makers for reference and mapping purposes, and may be used for basic applications such as viewing, querying, and map output production, or to provide a basemap to support graphical overlays and analysis with other spatial data. California, Metropolitan Transportation Commission. (2002). Census Places, 1990 - San Francisco Bay Area, California. MTC. Available at: http://purl.stanford.edu/th890tz9933. This layer is presented in the WGS84 coordinate system for web display purposes. Downloadable data are provided in native coordinate system or projection.

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  8. Title: Census Block Groups, 2000 - San Francisco Bay Area, California

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    Summary: This polygon shapefile displays U.S. Census Block Groups for the San Francisco Bay Area in California as of January 1, 2000. Block Groups (BGs) are clusters of blocks within the same census tract having the same first digit of their 4-digit census block number. For example, block group 3 (BG 3) within a census tract includes all blocks numbered from 3000 to 3999. Census 2000 BGs generally contain between 600 and 3,000 people, with an optimum size of 1,500 people. Most BGs were delineated by local participants in the U.S. Census Bureau's Participant Statistical Areas Program. The U.S. Census Bureau delineated BGs only where a local or tribal government declined to participate or where the U.S. Census Bureau could not identify a potential local participant.A BG usually covers a contiguous area. Each census tract contains at least one BG and BGs are uniquely numbered within census tract. Within the standard census geographic hierarchy BGs never cross county or census tract boundaries, but may cross the boundaries of county subdivisions, places, urbanized areas, voting districts, congressional districts, and American Indian/Alaska Native areas/Hawaiian home lands. Under the Census 2000 American Indian/Alaska Native area/Hawaiian homeland census geographic hierarchy, census tracts and BGs are defined within American Indian entities and can cross state and county boundaries. These are commonly referred to as Tribal BGs.BGs have a valid range of 0 through 9. BGs beginning with a 0 generally are in coastal and Great Lakes water and territorial seas. Rather than extending a census tract boundary into the Great Lakes or out to the three mile territorial sea limit, the U.S. Census Bureau delineated some census tract boundaries along the shoreline or just offshore. The U.S. Census Bureau assigned a default census tract number of 0000 and BG of 0 to the offshore areas not included in regularly numbered census tract areas.In decennial census data tabulations, a block group may be split to present data for every unique combination of county subdivision, place, voting district, congressional district, American Indian area/Alaska Native area/ Hawaiian home land shown in the data tabulation products. This layer is part of the Bay Area Metropolitan Transportation Commission (MTC) GIS Maps and Data collection. This dataset is intended for researchers, students, and policy makers for reference and mapping purposes, and may be used for basic applications such as viewing, querying, and map output production, or to provide a basemap to support graphical overlays and analysis with other spatial data. California, Metropolitan Transportation Commission. (2002). Census Block Groups, 2000 - San Francisco Bay Area, California. MTC. Available at: http://purl.stanford.edu/nk081sx0125. This layer is presented in the WGS84 coordinate system for web display purposes. Downloadable data are provided in native coordinate system or projection.

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  9. Title: UA Census Places, 1990 - South Dakota

    Contributors:

    Summary: This datalayer displays the Census Places for the state based on the ground condition of January 1, 1990. Places, for the reporting of decennial census data, include census designated places, consolidated cities, and incorporated places. Each place is assigned a five-digit Federal Information Processing Standards (FIPS) code, based on the alphabetical order of the place name within each state. If place names are duplicated within a state, and they represent distinctly different areas, a separate code is assigned to each place name alphabetically by primary county in which each place is located, or if both places are in the same county, alphabetically by their legal description (for example, ''city'' before ''village''). Statistical entities which may be represented in this datalayer include: Census Designated Place (CDP). Census designated places (CDPs) are delineated for each decennial census as the statistical counterparts of incorporated places. CDPs are delineated to provide census data for concentrations of population, housing, and commercial structures that are identifiable by name but are not within an incorporated place. CDP boundaries usually are defined in cooperation with state, local, and tribal officials. These boundaries, which usually coincide with visible features or the boundary of an adjacent incorporated place or other legal entity boundary, have no legal status, nor do these places have officials elected to serve traditional municipal functions. CDP boundaries may change from one decennial census to the next with changes in the settlement pattern; a CDP with the same name as in an earlier census does not necessarily have the same boundary. Consolidated City. An incorporated place that has combined its governmental functions with a county or subcounty entity but contains one or more other incorporated places that continue to function as local governments within the consolidated government. Incorporated Place. A type of governmental unit, incorporated under state law as a city, town (except in New England, New York, and Wisconsin), borough (except in Alaska and New York), or village, having legally prescribed limits, powers, and functions.

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  10. Title: UA Census Tracts, 2000 - Indiana

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    Summary: This datalayer displays Census Tracts for the state, based on boundaries established on January 1, 2000. Census tracts are small, relatively permanent statistical subdivisions of a county (or statistical equivalent of a county), and are defined by local participants as part of the U.S. Census Bureau's Participant Statistical Areas Program. The U.S. Census Bureau delineated the census tracts in situations where no local participant existed or where local or tribal governments declined to participate. The primary purpose of census tracts is to provide a stable set of geographic units for the presentation of decennial census data. Census 2000 is the first decennial census for which the entire United States has census tracts. In 1990 some counties had census tracts and others had block numbering areas (BNAs). In preparation for Census 2000, all BNAs were replaced by census tracts. Block groups and census blocks are uniquely numbered within census tract (except for Census 2000 collection blocks which were uniquely numbered within county). Census tracts generally have a population size between 1,500 and 8,000 people, with an optimum size of 4,000 people. When first delineated, census tracts are designed to be homogeneous with respect to population characteristics, economic status, and living conditions. The spatial size of census tracts varies widely depending on the density of settlement. Census tract boundaries are delineated with the intention of being maintained over a long time so that statistical comparisons can be made from census to census. However, physical changes in street patterns caused by highway construction, new development, and so forth, may require boundary revisions. In addition, census tracts occasionally are split due to population growth, or combined as a result of substantial population decline. Boundaries and Boundary Changes Census tract boundaries generally follow visible and identifiable features. Census tract boundaries may follow legal boundaries, such as minor civil division (MCD) or incorporated place boundaries, in some states and situations to allow for census tract-to-governmental unit relationships where the governmental boundaries tend to remain unchanged between censuses. State and county boundaries are al-ways census tract boundaries in the standard census geographic hierarchy. Under the Census 2000 American Indian/Alaska Native area/Hawaiian home land census geographic hierarchy, tribal census tracts are defined within American Indian entities and can cross state and county boundaries. In a few rare instances, a census tract may consist of discontiguous areas. These discontiguous areas may occur where the census tracts are coextensive with all or parts of legal entities that are themselves discontiguous. Census Tracts in American Indian Areas The U.S. Census Bureau has reserved the census tract numbering range of 9400 to 9499 for use by American Indian area participants in situations where an American Indian entity crosses county or state boundaries. Under the Census 2000 American Indian/Alaska Native area/Hawaiian home land census geographic hierarchy, the U.S. Census Bureau will tabulate census tract data within federally recognized American Indian reservations and off-reservation trust lands ignoring state and county boundaries. These are commonly referred to as tribal census tracts.

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  11. Title: UA Census Public Use Microdata Areas, 2000 - Iowa

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    Summary: This datalayer displays the Public Use Microdata Areas (PUMAs) for the state. A public use microdata area is a decennial census area for which the U.S. Census Bureau provides selected extracts of raw data from a small sample of long-form census records that are screened to protect confidentiality. These extracts are referred to as Public Use Microdata Sample (PUMS) files. Since 1960, data users have been using these files to create their own statistical tabulations and data summaries. For Census 2000, state, District of Columbia, and Puerto Rico participants, following U.S. Census Bureau criteria, delineated two types of PUMAs within their states or statistically equivalent entity. PUMAs of one type comprise areas that contain at least 100,000 people. The PUMS files for these PUMAs contain a 5-percent sample of the long-form records. The other type of PUMAs, super-PUMAs, comprise areas of at least 400,000 people. The sample size is 1-percent for the PUMS files for super-PUMAs. PUMAs cannot be in more than one state or statistically equivalent entity. The larger 1-percent PUMAs are aggregations of the smaller 5-percent PUMAs. The UA Census 2000 TIGER/Line files contain a Public Use Microdata Area File, 2000 field containing the PUMA codes from the 5- percent sample.

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  12. Title: UA Census Unified School Districts, 2000 - Minnesota

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    Summary: This datalayer displays the Unified School Districts for the entire state. A unified school district is inclusive of kindergarten through twelfth grade. School districts are geographic entities within which state, county, tribal, or local officials provide public educational services for the area's residents. The U.S. Census Bureau obtains the boundaries and names for school districts from state officials. The UA Census 2000 TIGER/Line files contain school district information from the 1999-2000 school year. The UA Census 2000 TIGER/Line files identify three levels of school districts representing different grade ranges of the school-age population (elementary and secondary) and a unified category to identify those school districts that represent all grade levels. The elementary and secondary levels of a school district can overlap each other because they represent different segments of the school-age population; for example, a secondary school district could cover parts of several elementary school districts. The TIGER/Line files use separate fields to accommodate for the overlap and may not contain a code for all grade levels. The TIGER/Line files contain a Unified School District code for those school districts where all grade levels are represented in a single district. The elementary and secondary school district code fields are blank if there is a unified school district code. An exception exists for the State of Hawaii and the five boroughs of New York city where the National School District Program requested that the U.S. Census Bureau include the School Complex Areas in Hawaii and the Community School Districts in New York city. In Massachusetts. South Carolina, and Tennessee some unified school districts also serve as secondary school districts in areas where there are elementary school districts. In these situations, the U.S. Census Bureau could not use the same school district code to identify school districts serving different grade ranges and has assigned two separate codes; a unified school district code and a separate 'false' secondary school district code. Data users can identify the 'false' school districts by looking for 'false' as part of the school district name appearing in Record Type C. A few additional exceptions occur where the Department of Defense operates elementary schools within a unified school district. The TIGER/Line files store the school district codes in a set of three, 5-character fields. All codes consist of numeric characters. The value, 99999, is a pseudo-school district code assigned to non-water blocks for which the National School District Program does not report a school district. Some large water areas have a pseudo-school district code of 99998.

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  13. Title: UA Census American Indian Reservations, 1990 - Texas

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    Summary: This datalayer depicts feature location and other associated data for American Indian tribal entities for those entities established on January 1, 1990. American Indian Reservations are areas that have been set aside by the United States for the use of tribes, the exterior boundaries of which are more particularly defined in the final tribal treaties, agreements, executive orders, federal statutes, secretarial orders, or judicial determinations. The Census Class Code range associated with American Indian Reservations is 0001 to 4989 for the 1990 datalayer. The U.S. Census Bureau recognizes federal reservations as territory over which American Indian tribes have primary governmental authority. These entities are known as colonies, communities, pueblos, rancherias, ranches, reservations, reserves, villages, Indian communities, and Indian villages. The Bureau of Indian Affairs (BIA) maintains a list of federally recognized tribal governments. The U.S. Census Bureau contacts representatives of American Indian tribal governments to identify the boundaries for federal reservations. Federal reservations may cross state, county, county subdivision, and place boundaries. The BIA supplied the U.S. Census Bureau with the names and exterior boundaries of the federal AIRs used for the 1990 census. The U.S. Census Bureau first reported data for American Indian reservations in the 1970 census. There are both legal and statistical American Indian, Alaska Native, and native Hawaiian entities for which the U.S. Census Bureau provides data. The legal entities consist of federally recognized American Indian reservations and off-reservation trust land areas, the tribal subdivisions that can divide these entities, state recognized American Indian reservations, Alaska Native Regional Corporations (ANRCs), and Hawaiian home lands (HHLs). The statistical entities are Alaska Native village statistical areas (ANVSAs), Oklahoma tribal statistical areas (OTSAs), tribal designated statistical areas (TDSAs), and state designated American Indian statistical areas (SDAISAs). Tribal subdivisions can exist within the statistical Oklahoma tribal statistical areas. In all cases, these areas are mutually exclusive in that no American Indian, Alaska Native, or Hawaiian home land can overlap another tribal entity, except for tribal subdivisions, which subdivide some American Indian entities, and Alaska Native village statistical areas (ANVSAs), which exist within Alaska Native Regional Corporations (ANRCs). American Indian Trust Lands Areas for which the United States holds title in trust for the benefit of a tribe (tribal trust land) or for an individual Indian (individual trust land). Trust lands can be alienated or encumbered only by the owner with the approval of the Secretary of the Interior or his/her authorized representative. Trust lands may be located on or off a reservation. The U.S. Census Bureau recognizes and tabulates data for reservations and off-reservation trust lands because American Indian tribes have primary governmental authority over these lands. Primary tribal governmental authority generally is not attached to tribal lands located off the reservation until the lands are placed in trust. In U.S. Census Bureau data tabulations, off-reservation trust lands always are associated with a specific federally recognized reservation and/or tribal government. A tribal government appointed liaison provides the name and boundaries of their trust lands. The Bureau of Indian Affairs (BIA), an agency in the U.S. Department of the Interior, identified and provided maps of these areas for use by the U.S. Census Bureau for the 1990 census. The U.S. Census Bureau first reported data for off-reservation tribal trust lands in the 1980 census; in 1990, the trust land data included both tribal and individual trust lands. The U.S. Census Bureau does not identify fee land (or land in fee simple status) or restricted fee lands as specific geographic categories and they are not identified in the TIGER/Line files. Trust lands are assigned the same code as the reservation with which they are associated. Trust lands associated with tribes that do not have a reservation are assigned codes based on tribal name. In the TIGER/Line files, a letter code-'T' for tribal and 'I' for individual-appears in a separate field and identifies off-reservation trust lands. American Indian Reservations-State (State AIRs) Reservations established by some state governments for tribes recognized by the state. A governor-appointed state liaison provides the names and boundaries for state recognized American Indian reservations to the U.S. Census Bureau. State reservations may cross county, county subdivision, and place boundaries. American Indian Tribal Subdivisions Administrative subdivisions of federally recognized American Indian reservations, off-reservation trust land, or Oklahoma tribal statistical areas (OTSAs). Tribal subdivisions are known as areas, chapters, communities, or districts. These entities are internal units of self-government or administration that serve social, cultural, and/or economic purposes for the American Indians on the reservations, off-reservation trust lands, or OTSAs. The U.S. Census Bureau obtains the boundary and name information for tribal subdivisions from tribal governments. The U.S. Census Bureau first provided data for American Indian tribal subdivisions in 1980 when it identified them as 'American Indian sub-reservation areas.' The U.S. Census Bureau did not provide data for American Indian tribal subdivisions in conjunction with the 1990 census. Joint Use Areas As applied to any American Indian area/Alaska Native area by the U.S. Census Bureau, means an area that is administered jointly and/or claimed by two or more American Indian tribes. The U.S. Census Bureau designates both legal and statistical joint use areas as unique geographic entities for the purpose of presenting statistical data. Tribal Designated Statistical Areas (TDSAs) Statistical entities identified and delineated for the U.S. Census Bureau by federally recognized American Indian tribes that do not currently have a federally recognized land base (reservation or off-reservation trust land). A TDSA generally encompasses a compact and contiguous area that contains a concentration of individuals who identify with a federally recognized American Indian tribe and in which there is structured or organized tribal activity. TDSAs are associated with Census Class Codes of 000 to 9989 for the 1990 datalayer. A TDSA may be located in more than one state, but it may not include area within an American Indian reservation, off-reservation trust land, Alaska Native village statistical area (ANVSA), or Oklahoma tribal statistical area (OTSA). The U.S. Census Bureau first reported data for TDSAs in conjunction with the 1990 census, when both federally and state recognized tribes could identify and delineate TDSAs. For Census 2000, TDSAs now apply only to federally recognized tribes. State recognized tribes without a land base, including those that were TDSAs in 1990, are identified as state designated American Indian statistical areas (SDAISAs), a new geographic entity for Census 2000. Tribal Jurisdiction Statistical Areas (TJSAs) 1990 statistical entities identified and delineated for the 1990 census to provide a geographic frame of reference for the presentation of statistical data. 1990 TJSA boundaries were required to follow census block boundaries and were based upon the boundaries of the former reservations of federally recognized tribes in Oklahoma. The range of Census Class Codes associated with TJSAs is 5000 to 5989. TJSAs replaced the Historic Areas of Oklahoma recognized by the U.S. Census Bureau for the 1980 decennial census. The 1990 descriptive designation, TJSA, has been changed for Census 2000 to Oklahoma tribal statistical areas (OTSAs).

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  14. Title: UA Census Landmark Line Features, 2000 - Louisiana

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    Summary: This datalayer displays landmark line features throughout the state. 'Landmark' is the general name given to a cartographic (or locational) landmark, a land-use area, and a key geographic location (KGL). A cartographic landmark is identified for use by an enumerator while working in the field. A land-use area is identified in order to minimize enumeration efforts in uninhabited areas or areas where human access is restricted. A key geographic location is identified in order to more accurately geocode and enumerate a place of work or residence. The only feature class represented in this layer has a CFCC of D51 which identifies that feature as an airport or airfield. Other possible landmark features could include military installations, multi-household or transient quarters, custodial facilities, educational or religious institutions, other types of transportation facilities or terminals, employment centers, towers, open space and other special landmark designations for post offices, police stations and firehouses.

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  15. Title: UA Census Landmark Line Features, 2000 - Texas

    Contributors:

    Summary: This datalayer displays landmark line features throughout the state. 'Landmark' is the general name given to a cartographic (or locational) landmark, a land-use area, and a key geographic location (KGL). A cartographic landmark is identified for use by an enumerator while working in the field. A land-use area is identified in order to minimize enumeration efforts in uninhabited areas or areas where human access is restricted. A key geographic location is identified in order to more accurately geocode and enumerate a place of work or residence. The only feature class represented in this layer has a CFCC of D51 which identifies that feature as an airport or airfield. Other possible landmark features could include military installations, multi-household or transient quarters, custodial facilities, educational or religious institutions, other types of transportation facilities or terminals, employment centers, towers, open space and other special landmark designations for post offices, police stations and firehouses.

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  16. Title: UA Census Water Bodies, 2000 - Ohio

    Contributors:

    Summary: This datalayer displays water bodies throughout the state. This category includes lakes, ponds, bays, rivers, reservoirs and other water features. Predominant features represented in this layer have Census Feature Class Codes (CFCCs) of: H01 (Shoreline of perennial water feature); H11 (Perennial stream or river); H12 (Intermittent stream, river, or wash); H21 (Perennial canal, ditch, or aqueduct); H31 (Perennial lake or pond); H41 (Perennial reservoir); H51 (Bay, estuary, gulf, or sound). The Feature Name attribute further identifies water bodies as rivers, creeks, branches, forks, etc.

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  17. Title: UA Census Tracts, 1990 - U.S. Minor Outlying Islands

    Contributors:

    Summary: This datalayer displays Census Tracts for the state, based on entity boundaries established on January 1, 1990. Census tracts are small, relatively permanent statistical subdivisions of a county (or statistical equivalent of a county), and are defined by local participants as part of the U.S. Census Bureau's Participant Statistical Areas Program. The U.S. Census Bureau delineated the census tracts in situations where no local participant existed or where local or tribal governments declined to participate. The primary purpose of census tracts is to provide a stable set of geographic units for the presentation of decennial census data. Census 2000 is the first decennial census for which the entire United States has census tracts. In 1990 some counties had census tracts and others had block numbering areas (BNAs). In preparation for Census 2000, all BNAs were replaced by census tracts. Block groups and census blocks are uniquely numbered within census tract (except for Census 2000 collection blocks which were uniquely numbered within county). Census tracts generally have a population size between 1,500 and 8,000 people, with an optimum size of 4,000 people. When first delineated, census tracts are designed to be homogeneous with respect to population characteristics, economic status, and living conditions. The spatial size of census tracts varies widely depending on the density of settlement. Census tract boundaries are delineated with the intention of being maintained over a long time so that statistical comparisons can be made from census to census. However, physical changes in street patterns caused by highway construction, new development, and so forth, may require boundary revisions. In addition, census tracts occasionally are split due to population growth, or combined as a result of substantial population decline. Boundaries and Boundary Changes Census tract boundaries generally follow visible and identifiable features. Census tract boundaries may follow legal boundaries, such as minor civil division (MCD) or incorporated place boundaries, in some states and situations to allow for census tract-to-governmental unit relationships where the governmental boundaries tend to remain unchanged between censuses. State and county boundaries are al-ways census tract boundaries in the standard census geographic hierarchy. Under the Census 2000 American Indian/Alaska Native area/Hawaiian home land census geographic hierarchy, tribal census tracts are defined within American Indian entities and can cross state and county boundaries. In a few rare instances, a census tract may consist of discontiguous areas. These discontiguous areas may occur where the census tracts are coextensive with all or parts of legal entities that are themselves discontiguous. Census Tracts in American Indian Areas The U.S. Census Bureau has reserved the census tract numbering range of 9400 to 9499 for use by American Indian area participants in situations where an American Indian entity crosses county or state boundaries. Under the Census 2000 American Indian/Alaska Native area/Hawaiian home land census geographic hierarchy, the U.S. Census Bureau will tabulate census tract data within federally recognized American Indian reservations and off-reservation trust lands ignoring state and county boundaries. These are commonly referred to as tribal census tracts.

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  18. Title: UA Census Counties, 1990 - Vermont

    Contributors:

    Summary: This datalayer displays the counties for the state, based on a ground condition of January 1, 1990. The primary legal divisions of most states are termed ''counties.'' Each county and statistically equivalent entity is assigned a three-digit Federal Information Processing Standards code that is unique within the state. These codes are assigned in alphabetical order of county or county equivalent within each state.

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  19. Title: UA Census Class A Roads, 2000 - Mississippi

    Contributors:

    Summary: This datalayer displays the Type A class roads thoughout the state. Feature Class A roads include: Primary roads with limited access (interstate highways, toll highways); Primary roads without limited access (US highways, some state highways and county highways that connect cities and larger towns); regional and state highways state highways, Secondary and connecting roads (includes mostly state highways, but may include some county highways that connect smaller towns, subdivisions, and neighborhoods); Local, neighborhood, and rural roads, city streets, and vehicular trails. The U.S. Census Bureau uses the term divided to refer to a road with opposing traffic lanes separated by any size median, and separated to refer to lanes that are represented in the Census TIGER database as two distinct complete chains. The term, rail line in center, indicates that a rail line shares the road right-of-way. The rail line may follow the center of the road or be directly next to the road; representation is dependent upon the available source used during the update. The rail line can represent a railroad, a streetcar line, or other carline. Road types possibly represented here are defined as follows: -Primary Highway With Limited Access (A1): Interstate highways and some toll highways are in this category and are distinguished by the presence of interchanges. These highways are accessed by way of ramps and have multiple lanes of traffic. The opposing traffic lanes are divided by a median strip. The TIGER/Line files may depict these opposing traffic lanes as two distinct lines in which case, the road is called separated. -Primary Road Without Limited Access (A2): This category includes nationally and regionally important highways that do not have limited access as required by category A1. It consists mainly of US highways, but may include some state highways and county highways that connect cities and larger towns. A road in this category must be hard-surface (concrete or asphalt). It has intersections with other roads, may be divided or undivided, and have multilane or single-lane characteristics. -Secondary and Connecting Road (A3): This category includes mostly state highways, but may include some county highways that connect smaller towns, subdivisions, and neighborhoods. The roads in this category are smaller than roads in Category A2, must be hard-surface (concrete or asphalt), and are usually undivided with single-lane characteristics. These roads usually have a local name along with a route number and intersect with many other roads and driveways. -Local, Neighborhood, and Rural Road (A4): A road in this category is used for local traffic and usually has a single lane of traffic in each direction. In an urban area, this is a neighborhood road and street that is not a thoroughfare belonging in categories A2 or A3. In a rural area, this is a short-distance road connecting the smallest towns; the road may or may not have a state or county route number. Scenic park roads, unimproved or unpaved roads,and industrial roads are included in this category. Most roads in the Nation are classified as A4 roads. -Vehicular Trail (A5): A road in this category is usable only by four-wheel drive vehicles, is usually a one-lane dirt trail, and is found almost exclusively in very rural areas. Sometimes the road is called a fire road or logging road and may include an abandoned railroad grade where the tracks have been removed. Minor, unpaved roads usable by ordinary cars and trucks belong in this category. -Road with Special Characteristics (A6): This category includes roads, portions of a road, intersections of a road, or the ends of a road that are parts of the vehicular highway system and that have separately identifiable characteristics. -Road as Other Thoroughfare (A7): A road in this category is not part of the vehicular highway system. It is used by bicyclists or pedestrians, and is typically inaccessible to mainstream motor traffic except for private-owner and service vehicles. This category includes foot and hiking trails located on park and forest land, as well as stairs or walkways that follow a road right-of-way and have names similar to road names.

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  20. Title: UA Census Counties, 2000 - Nebraska

    Contributors:

    Summary: This datalayer displays the counties for the state, based on a ground condition of January 1, 2000. The primary legal divisions of most states are termed ''counties.'' Each county and statistically equivalent entity is assigned a three-digit Federal Information Processing Standards code that is unique within the state. These codes are assigned in alphabetical order of county or county equivalent within each state.

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