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UA Census Zip Code Tabulation Areas, 2000 - Iowa
- Identification Information
- Data Quality Information
- Spatial Data Organization Information
- Spatial Reference Information
- Entity and Attribute Information
- Distribution Information
- Metadata Reference Information
- Identification Information
- Citation
- Originator
- U.S. Department of Commerce, Bureau of the Census, Geography Division
- Publication Date
- 2002
- Title
- UA Census Zip Code Tabulation Areas, 2000 - Iowa
- Edition
- UA Census 2000
- Geospatial Data Presentation Form
- vector digital data
- Collection Title
- TIGER/Line Files, UA Census 2000
- Publication Information
- Online Linkage
- https://hgl.harvard.edu/catalog/harvard-tg00iazcta
- Abstract
- The polygons in this datalayer represent ZIP Code Tabulation Areas (ZCTAs) for the entire state. ZCTAs are a new statistical entity developed by the U.S. Census Bureau for tabulating summary statistics from Census 2000. This new entity was developed to overcome the difficulties in precisely defining the land area covered by each ZIP Code. Defining the extent of an area is necessary in order to accurately tabulate census data for that area. ZCTAs are generalized area representations of U.S. Postal Service (USPS) ZIP Code service areas. Simply put, each one is built by aggregating the Census 2000 blocks, whose addresses use a given ZIP Code, into a ZCTA which gets that ZIP Code assigned as its ZCTA code. They represent the majority USPS five-digit ZIP Code found in a given area. For those areas where it is difficult to determine the prevailing five-digit ZIP Code, the higher-level three-digit ZIP Code is used for the ZCTA code. ZCTAs are created based on the following criteria: - ZCTAs follow census block boundaries. The ZCTA code for each census block generally represents the majority ZIP Code of the addresses within that census block. - ZCTAs are not exact representations of the USPS's ZIP Code delivery areas. - ZCTA codes cover all land and water areas. - ZCTAs include some dedicated post office box ZIP Codes in areas served only by post office boxes. - ZCTAs representing post office box ZIP Codes generally have more than 10 addresses. - ZCTAs exclude unique, single delivery point ZIP Codes, such as those for firms and organizations. - ZCTAs are distinct from other Census Bureau statistical areas, such as census tracts, because they are not stable over time and are computer-delineated based on the location of addresses at the time of Census 2000 rather than manually delineated by local program participants or Census Bureau staff before the census. - ZCTAs are distinct from other representations of ZIP Codes because they are based on address information and ZIP Codes collected or verified during Census 2000 operations. - ZCTAs frequently cross county and place boundaries and may occasionally cross from one state into another. ZCTAs are approximate area representations of United States Postal Service (USPS) ZIP Code service areas that the U.S. Census Bureau is creating for statistical purposes for Census 2000. Data users should not use ZCTAs to identify the official USPS ZIP Code for mail delivery. Each Census 2000 tabulation block will have a single ZCTA code that will reflect the majority ZIP Code for addresses within that tabulation block. A ZCTA may not exist for every USPS ZIP Code. For instance, a special purpose ZIP Code may represent a point location that does not characterize the majority of the addresses for a Census 2000 tabulation block. Under these circumstances the special purpose ZIP Code will not appear as a ZCTA. The U.S. Census Bureau will be identifying ZCTAs by using a five-character alpha-numeric code. The first three characters will represent the 3-digit ZIP Code and may contain leading zeros. For ZCTAs defined only by a 3-digit ZIP Code the last two characters of the ZCTA code will be "XX." For example, ZCTA code "290XX" will represent the generic 3-digit ZIP Code290 where no 5-digit ZIP Code was available. For ZCTA codes that will reflect the 5-digit ZIP Code, the last two characters of the ZCTA code will be numeric. For example, the ZCTA code "00601" will represent the 5-digit ZIP Code 00601. The ZCTA delineation process will not recognize ZCTA codes ending in "00", such as "29000", as valid 5-digit ZCTA codes. Some water features will have a 3-digit ZCTA code followed by "HH", for example "290HH". These codes will apply only to water features and usually will belong to water features located along the edges of 5-digit ZCTAs. The codes will indicate that the water feature does not clearly fall within one 5-digit ZCTA and is distinct from the 3-digit ZCTA code that will be assigned to land areas. In effect, these codes will identify unassigned water areas. The ZCTA delineation process will attempt to assign a 5-digit ZCTA code to areas with no ZIP Code or address data. Where reliable data are unavailable for extensive areas, the ZCTA code may represent the more general 3-digit ZIP Code.
- Purpose
- This layer 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. This layer will provide a basemap for layers related to socio-political anaylsis, statistical enumeration and analysis, or to support graphical overlays and analysis with other spatial data. More advanced user applications may focus on demographics, urban and rural land use planning, socio-economic analysis and related areas (including defining boundaries, managing assets and facilities, integrating attribute databases with geographic features, spatial analysis, and presentation output.)
- Supplemental Information
- The UA Census 2000 TIGER/Line files are extracts of selected geographic and cartographic information from the Census TIGER (Topologically Integrated Geographic Encoding and Referencing) database. The geographic coverage for a single TIGER/Line file is a county or statistical equivalent entity, with the coverage area based either on January 1, 2000 or January 1, 1990 legal boundaries. The Census TIGER database represents a seamless national file with no overlaps or gaps between parts. However, each county-based TIGER/Line file is designed to stand alone as an independent data set or the files can be combined to cover the whole nation and its territories. The UA Census 2000 TIGER/Line files consist of line segments representing physical features and governmental and statistical boundaries. The boundary information in the TIGER/Line files are for statistical data collection and tabulation purposes only; their depiction and designation for statistical purposes does not constitute a determination of jurisdictional authority or rights of ownership or entitlement. The files contain information distributed over a series of record types for the spatial objects of a county. There are 17 record types, including the basic data record, the shape coordinate points, and geographic codes that can be used with appropriate software to prepare maps. Other geographic information contained in the files includes attributes such as feature identifiers/census feature class codes (CFCC) used to differentiate feature types, address ranges and ZIP Codes, codes for legal and statistical entities, latitude/longitude coordinates of linear and point features, landmark point features, area landmarks, key geographic features, and area boundaries. The UA Census 2000 TIGER/Line data dictionary contains a complete list of all the fields in the 17 record types. For additional information on this or other layers in the UA Census 2000 TIGER dataset please consult the U.S. Census Bureau's technical documentation at: http://www.census.gov/geo/www/tiger/tigerua/ua2ktgr.pdf
- Temporal Extent
- Currentness Reference
- ground condition
- Time Instant
- 20000101
- Bounding Box
- West
- -96.639705
- East
- -90.1453939996473
- North
- 43.501196
- South
- 40.375437
- ISO Topic Category
- location
- boundaries
- Theme Keyword
- Census
- Zip codes
- Boundaries
- Theme Keyword Thesaurus
- LCSH
- Theme Keyword
- Zip Code Tabulation Areas
- Theme Keyword Thesaurus
- None
- Place Keyword
- Iowa
- Place Keyword Thesaurus
- GNIS
- Temporal Keyword
- Access Restrictions
- None
- Use Restrictions
- For educational, non-commercial use only. TIGER, TIGER/Line, and Census TIGER are trademarks of the Bureau of the Census. Although this data set has been developed by the U.S. Census Bureau, no warranty expressed or implied is made by the Bureau as to the accuracy of the data and related materials. The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the Bureau in the use of this data, or related materials.
- Status
- Complete
- Maintenance and Update Frequency
- Datalayers derived from TIGER/Line files are extracted from the Census TIGER data base when needed for geographic programs required to support the census and survey programs of the Census Bureau. No changes or updates will be made to the UA Census 2000 TIGER/Line files.
- Point of Contact
- Contact Organization
- U.S. Department of Commerce, Bureau of the Census, Geography Division
- Delivery Point
- 8903 Presidential Pkwy, Room 303 WP I
- Delivery Point
- Bureau of the Census
- Delivery Point
- 4700 Silver Hill Road, Stop 7400
- City
- Upper Marlboro
- City
- Washington
- State
- Maryland
- State
- District of Columbia
- Postal Code
- 20772
- Postal Code
- 20233-7400
- Country
- USA
- Country
- USA
- Contact Telephone
- 1-301-457-1128
- Contact Facsimile Telephone
- 1-301-457-4710
- Contact Electronic Mail Address
- tiger@census.gov
- Hours of Service
- Monday through Friday 8:30 A.M. to 4:30 P.M. EST-USA
- Credit
- U.S. Department of Commerce, Bureau of the Census, Geography Division.
- Native Data Set Environment
- Microsoft Windows NT Version 4.0 (Build 1381) Service Pack 6; ESRI ArcCatalog 8.2.0.700
- Collection
- Originator
- U.S. Department of Commerce, Bureau of the Census, Geography Division
- Publication Date
- 2002
- Title
- TIGER/Line Files, UA Census 2000
- Edition
- UA Census 2000
- Publication Information
- Publication Place
- Washington, DC
- Publisher
- U.S. Department of Commerce, Bureau of the Census
- Data Quality Information
- Attribute Accuracy Report
- Topological Properties The attribute accuracy of the TIGER/Line files is as precise as the source used during the creation or update of the Census TIGER database. Accuracy statements on the Census TIGER database are based on deductive estimates; no specific field tests for attribute accuracy have been conducted on the files. However, updates or corrections resulting from normal U.S. Census Bureau field operations are entered into the Census TIGER database. In addition, quality checks are conducted to verify clerical transcription of data from source materials. Based on past experience, attribute codes match the source materials with less than a two-percent error. The feature network of complete chains (as represented by Record Types 1 and 2) is complete for census purposes. Data users should be aware that on occasion they might not be able to trace a specific feature by name or by census feature class code (CFCC) as a continuous line throughout the TIGER/Line files without making additional edits. For example, State Highway 32 may cross the entire county. The TIGER/Line files will contain complete chains in the file at the location of State Highway 32, but the complete chains may individually have one of a collection of local names such as S Elm Street, or Smallville Highway, with or without State Highway 32 as an alternate. The most frequent CFCC for a state highway is A21, but the complete chains at the location of State Highway 32 may have a variety of class codes such as A01, A41, or A21. Recent edits have reduced this problem, but not eliminated it. Boundaries and Geographic Entity Codes The U.S. Census Bureau collects and tabulates information for both legal and statistical entities. Record Type 1 mainly identifies the boundaries and codes for the legal entities reported to the U.S. Census Bureau to be legally in effect as of the Census 2000 Boundary and Annexation Survey. Record Types 3 and A generally contain the 1990 census tabulation geographic boundaries and codes for those entities. Most legal boundaries are based on the annotations made by local officials in response to the U.S. Census Bureau's Boundary and Annexation Surveys. The boundary information in the TIGER/Line files are for statistical data collection and tabulation purposes only; their depiction and designation for statistical purposes does not constitute a determination of jurisdictional authority or rights of ownership or entitlement. Local data users generally define and delineate statistical entities following U.S. Census Bureau guidelines. However, there are several exceptions: - The U.S. Census Bureau defines Urbanized Areas (UAs) based strictly on technical considerations. USGS edited the FIPS 55 file to ensure alphabetical sorting and data consistency. As a result, changes were made to the FIPS 55 codes and related class codes. These changes, plus codes for new Census 2000 entities, appear in Record Type C. Other attribute data in the TIGER/Line files were gathered from many sources. The U.S. Census Bureau's staff linked the attribute information to the spatial framework of features. Most procedures for gathering the needed attributes were clerical. The quality of these attributes was ensured by various tests conducted before, during, and after the time that the attribute information was entered into the Census TIGER database. Tests included source material selection and evaluation checks, quality control checks on staff work, independent reviews by local and tribal leaders of maps produced from the Census TIGER database, and staff reviews of computer-performed operations. - The U.S. Census Bureau defines ZIP Code Tabulation Areas (ZCTAs) through an automated process utilizing addresses in the TIGER database and the Master Address File (MAF). - State Departments of Education delineate school districts. - The designated liaison for the Redistricting Data Program supplies Voting Districts (VTDs) and State Legislative Districts (SLDs). - Metropolitan Planning Organizations or State Departments of Transportation define Traffic Analysis Zones (TAZs). The USGS maintains the file that is published as FIPS 55. The U.S. Census Bureau uses the file for coding American Indian/Alaska Native Areas, county subdivisions, consolidated cities, places, and sub-MCDs. Address Ranges and ZIP Codes The conversion from the Geographic Base File/Dual Independent Map Encoding (GBF/DIME)-Files to the TIGER format involved neither verification of previously existing address ranges nor any significant updates or corrections. Prior to the release of the 1992 TIGER/Line files, the address ranges for an area were generally the same as those in the corresponding 1980 GBF/DIME-File. The 1992 TIGER/Line files included ACF address ranges for existing and new features identified during census operations. Address ranges and ZIP Codes were verified and coverage extended for Census 2000 through the use of the Master Address File (MAF). The MAF is closely linked to the Census TIGER database. Local address lists and addresses from the U.S. Postal Service supplement the MAF. Through an automated matching process, addresses in the MAF were compared to existing address ranges in the Census TIGER database creating or modifying the TIGER address ranges where necessary. Feature Identifiers A national consistency review of all feature names in the Census TIGER database was performed by running a revised name standardizing operation on all feature identifiers. An additional benefit was the removal of nonstandard characters and punctuation from the names. To improve accuracy, road names in the Census TIGER database were compared with street names in the ZIP+4 file from the US Postal Service. Errors in feature directionals or feature types were corrected in the Census TIGER database.
- Logical Consistency Report
- Node-line-area relationships satisfy topological requirements. These requirements include the following: - Complete chains must begin and end at nodes. - Complete chains must connect to each other at nodes. - Complete chains do not extend through nodes. - Left and right polygons are defined for each complete chain element and are consistent for complete chains connecting at nodes. - Complete chains representing the limits of a file are free from gaps. The U.S. Census Bureau performed automated tests to ensure logical consistency and limits of file. Some polygons in the TIGER/Line files are so small that the polygon internal point has been manually placed on a node that defines the polygon perimeter. The U.S. Census Bureau uses it's internally developed Geographic Update System to enhance and modify spatial and attribute data in the Census TIGER database. The Census TIGER database has two generations of currency in geographic areas. These are the 1990 census areas and the Census 2000 areas. The location, type, and number of areas affect the boundaries of geographic areas. To prepare for Census 2000, those features used only as boundaries in the 1980 census were deleted. The deletions lowered the overall count of complete chains and polygons. Standard geographic codes, such as FIPS codes for states, counties, municipalities, and places, are used when encoding spatial entities. The U.S. Census Bureau performed spatial data tests for logical consistency of the codes during the compilation of the original Census TIGER database files. Most of the codes themselves were provided to the U.S. Census Bureau by the U.S. Geological Survey (USGS), the agency responsible for maintaining FIPS 55.
- Completeness Report
- Data completeness of the TIGER/Line files reflects the contents of the Census TIGER data base at the time the TIGER/Line files (UA 2000 version) were created. The GBF/DIME-Files and the USGS's DLG were the two main sources of spatial attribute data. Data for a given category contain attribute codes that reflect the information portrayed on the original source. The TIGER/Line files also use the U.S. Census Bureau's internal coding scheme which in some cases parallels the FIPS codes. The feature network of complete chains is complete for census purposes. For the 1990 census and Census 2000, census enumerators identified new and previously unreported street features for the entire nation during a series of decennial census operations. In some areas, local officials reviewed the census maps and identified new features and feature changes. The TIGER/Line files contain limited point and area landmark data. The enumerator updates for decennial censuses do not stress landmark features. Computer file matching and automated updates from the Economic and Agriculture censuses added landmarks and key geographic locations (KGLs).
- Horizontal Positional Accuracy Report
- The U.S. Census Bureau's mission to count and profile the Nation's people and institutions does not require very high levels of positional accuracy in its geographic products. Its files and maps are designed to show only the relative positions of elements. Coordinates in the TIGER/Line files are in decimal degrees and have six implied decimal places. The positional accuracy of these coordinates is not as great as the six decimal places suggest. The positional accuracy varies with the source materials used, but at best meets the established National Map Accuracy standards (approximately + /- 167 feet) where 1:100,000-scale maps from the USGS are the source. The U.S. Census Bureau cannot specify the accuracy of feature updates added by its field staff or of features derived from the GBF/DIME-Files or other map or digital sources. Thus, the level of positional accuracy in the TIGER/Line files is NOT suitable for high-precision measurement applications such as engineering problems, property transfers, or other uses that might require highly accurate measurements of the earth's surface. Despite the fact that TIGER/Line data positional accuracy is not as high as the coordinate values imply, the six-decimal place precision is useful when producing maps. This precision allows you to place features that are next to each other on the ground in the correct position, relative to each other, on the map without overlap.
- Lineage
- Source
- Originator
- U.S. Department of Commerce, Bureau of the Census, Geography Division
- Publication Date
- Unpublished Material
- Title
- Census TIGER database
- Edition
- UA Census 2000
- Source Scale Denominator
- 100000
- Type of Source Media
- online
- Source Temporal Extent
- Time Period Information
- Single Date/Time
- Calendar Date
- 2000
- Source Currentness Reference
- Date the file was made available to create TIGER/Line File extracts.
- Contribution
- Selected geographic and cartographic information (line segments) from the Census TIGER database.
- Spatial Data Organization Information
- Direct Spatial Reference Method
- Vector
- Point and Vector Object Information
- SDTS Terms Description
- SDTS Point and Vector Object Type
- G-polygon
- Point and Vector Object Count
- 1519
- Spatial Reference Information
- Horizontal Coordinate System Definition
- Geographic
- Latitude Resolution
- 0.000000
- Longitude Resolution
- 0.000000
- Geographic Coordinate Units
- Decimal degrees
- Geodetic Model
- Horizontal Datum Name
- North American Datum of 1927
- Ellipsoid Name
- Clarke 1866
- Semi-major Axis
- 6378206.400000
- Denominator of Flattening Ratio
- 294.978698
- Vertical Coordinate System Definition
- Altitude System Definition
- Altitude Resolution
- 1.000000
- Altitude Encoding Method
- Explicit elevation coordinate included with horizontal coordinates
- Entity and Attribute Information
- Entity Type
- Entity Type Label
- UA Census Zip Code Tabulation Areas, 2000 - Iowa
- Entity Type Definition
- ESRI Shapefile. Polygons represent feature areas
- Entity Type Definition Source
- ESRI, Census
- Attributes
- GIST_ID
- Internal Feature Identifier
- Definition Source
- Department of Commerce, ESRI
- COUNTY
- Numeric Code combining State, County digits (Federal Information Processing StandardsNational Institute of Standards and Technology)
- Definition Source
- Department of Commerce, National Institute of Standards and Technology
- ZCTA
- Zip Code Tabulation Area Code (Federal Information Processing StandardsNational Institute of Standards and Technology) (National 5-Digit ZIP Code and Post Office Directory (Publication 65)United States Postal Service)
- Definition Source
- U.S. Postal Service; Department of Commerce, Census Bureau
- SHAPE
- Feature geometry. (Coordinates defining the features.)
- Definition Source
- ESRI
- SHAPE.AREA
- Area of feature in square coverage units
- Positive real numbers
- Definition Source
- Computed
- SHAPE.LEN
- Feature length in map units
- Positive real numbers
- Definition Source
- Computed
- SHAPE.FID
- Internal feature number. (Sequential unique whole numbers that are automatically generated.)
- Definition Source
- ESRI
- Distribution Information
- Format Name
- Shape
- Distributor
- Harvard Geospatial Library
- Name
- Metadata Reference Information
- Metadata Date
- 20030730
- Metadata Contact
- Contact Information
- Contact Person Primary
- Contact Person
- Contact Organization
- Harvard Geospatial Library
- Contact Address
- Address
- Harvard University Library
- Address
- Office For Information Systems
- Address
- 1280 Massachusetts Avenue
- City
- Cambridge
- State or Province
- MA.
- Postal Code
- 02138
- Country
- USA
- Contact Voice Telephone
- 617-495-2417
- Contact Facsimile Telephone
- 617-496-0440
- Contact Electronic Mail Address
- hgl_ref@hulmail.harvard.edu
- Metadata Standard Name
- FGDC Content Standards for Digital Geospatial Metadata
- Metadata Standard Version
- FGDC-STD-001-1998
- Metadata Extensions
- Online Linkage
- http://www.esri.com/metadata/esriprof80.html
- Profile Name
- ESRI Metadata Profile
