README for “Counties 1995-Present” dataset. U.S. Department of Commerce (DOC), United States Census Bureau (USCB); U.S. Department of Transportation (USDOT), Bureau of Transportation Statistics (BTS) [distributor] 2025-05-29 ---------------------------------------------------------------- LINKS TO DATASET ---------------------------------------------------------------- A. Dataset archive link: https://doi.org/10.21949/1520800 B. NTAD catalog dataset link (Current Year): https://doi.org/10.21949/1522038 ---------------------------------------------------------------- SUMMARY OF DATASET ---------------------------------------------------------------- The Counties 1995-Present dataset is from the United States Census Bureau (USCB), and is part of the U.S. Department of Transportation (USDOT)/Bureau of Transportation Statistics’s (BTS's) National Transportation Atlas Database (NTAD). This resource is a member of a series. The TIGER/Line shapefiles and related database files (.dbf) are an extract of selected geographic and cartographic information from the U.S. Census Bureau's Master Address File / Topologically Integrated Geographic Encoding and Referencing (MAF/TIGER) Database (MTDB). The MTDB represents a seamless national file with no overlaps or gaps between parts, however, each TIGER/Line shapefile is designed to stand alone as an independent data set, or they can be combined to cover the entire nation. The primary legal divisions of most states are termed counties. In Louisiana, these divisions are known as parishes. In Alaska, which has no counties, the equivalent entities are the organized boroughs, city and boroughs, municipalities, and for the unorganized area, census areas. The latter are delineated cooperatively for statistical purposes by the State of Alaska and the Census Bureau. In four states (Maryland, Missouri, Nevada, and Virginia), there are one or more incorporated places that are independent of any county organization and thus constitute primary divisions of their states. These incorporated places are known as independent cities and are treated as equivalent entities for purposes of data presentation. The District of Columbia and Guam have no primary divisions, and each area is considered an equivalent entity for purposes of data presentation. The Census Bureau treats the following entities as equivalents of counties for purposes of data presentation: Municipios in Puerto Rico, Districts and Islands in American Samoa, Municipalities in the Commonwealth of the Northern Mariana Islands, and Islands in the U.S. Virgin Islands. The entire area of the United States, Puerto Rico, and the Island Areas is covered by counties or equivalent entities. ---------------------------------------------------------------- TABLE OF CONTENTS ---------------------------------------------------------------- A. General Information B. Sharing/Access & Policies Information C. Data and Related File Overview D. Methodological Information E. Data-Specific Information for: Counties 1995-Present [datasets] F. Update Log ---------------------------------------------------------------- A. GENERAL INFORMATION ---------------------------------------------------------------- 0. Title of Dataset: Counties 1995-Present [dataset] 1. Description of Dataset: The Counties 1995-Present dataset is from the United States Census Bureau (USCB), and is part of the U.S. Department of Transportation (USDOT)/Bureau of Transportation Statistics’ (BTS's) National Transportation Atlas Database (NTAD). This resource is a member of a series. The TIGER/Line shapefiles and related database files (.dbf) are an extract of selected geographic and cartographic information from the U.S. Census Bureau's Master Address File / Topologically Integrated Geographic Encoding and Referencing (MAF/TIGER) Database (MTDB). The MTDB represents a seamless national file with no overlaps or gaps between parts, however, each TIGER/Line shapefile is designed to stand alone as an independent data set, or they can be combined to cover the entire nation. The primary legal divisions of most states are termed counties. In Louisiana, these divisions are known as parishes. In Alaska, which has no counties, the equivalent entities are the organized boroughs, city and boroughs, municipalities, and for the unorganized area, census areas. The latter are delineated cooperatively for statistical purposes by the State of Alaska and the Census Bureau. In four states (Maryland, Missouri, Nevada, and Virginia), there are one or more incorporated places that are independent of any county organization and thus constitute primary divisions of their states. These incorporated places are known as independent cities and are treated as equivalent entities for purposes of data presentation. The District of Columbia and Guam have no primary divisions, and each area is considered an equivalent entity for purposes of data presentation. The Census Bureau treats the following entities as equivalents of counties for purposes of data presentation: Municipios in Puerto Rico, Districts and Islands in American Samoa, Municipalities in the Commonwealth of the Northern Mariana Islands, and Islands in the U.S. Virgin Islands. The entire area of the United States, Puerto Rico, and the Island Areas is covered by counties or equivalent entities. 2. Dataset archive link: https://doi.org/10.21949/1520800 3. Authorship Information: Principal Data Creator or Data Manager Contact Information Institution: U.S. Department of Commerce (DOC), United States Census Bureau (USCB) Address: 4600 Silver Hill Rd., Washington D.C. 20233 Contact: geo.bas@census.gov/geo.geography@census.gov Data Distributor Contact Information Name: National Transportation Atlas Database (NTAD) Institution: U.S. Department of Transportation (USDOT), Bureau of Transportation Statistics (BTS), Office of Spatial Analysis and Visualization (OSAV) Address: 1200 New Jersey Ave. SE, Washington D.C. 20590 Email: ntad@dot.gov 4. Date of data collection and update interval: There are no planned updates to this dataset. 5. Geographic location of data collection: United States of America 6. Information about funding sources that supported the collection of the data: United States Census Bureau (USCB), U.S. Department of Commerce (DOC) ---------------------------------------------------------------- B. SHARING/ACCESS & POLICIES INFORMATION ---------------------------------------------------------------- 0. Recommended citation for the data: U.S. Department of Commerce (DOC), United States Census Bureau (USCB), U.S. Department of Transportation, Bureau of Transportation Statistics (BTS) [distributor]. Counties 1995-Present [datasets]. https://doi.org/10.21949/1520800 1. Licenses/restrictions placed on the data: These data are in the Public Domain. 2. Was data derived from another source?: No. 3.This document was created to meet the requirements enumerated in the U.S. Department of Transportation's 'Plan to Increase Public Access to the Results of Federally-Funded Scientific Research' Version 1.1 << https://doi.org/10.21949/1520559 >> and guidelines suggested by the DOT Public Access website << https://doi.org/10.21949/1503647 >>, in effect and current as of December 03, 2020. ---------------------------------------------------------------- C. DATA & RELATED FILE OVERVIEW ---------------------------------------------------------------- 1. File List for the Counties 1995-Present dataset A. Filename: Counties_NTAD1995_Present.zip and Counties_Political_NTAD1995_NTAD2015 Short description: Compressed file folders containing the geospatial data for Counties 1995-Present dataset. File folders are classified by NTAD publication year. B. Filename: bts_NTAD_Counties_DMP_20250529.pdf Short description: A PDF file containing the Data Management Plan that was created for current and future management of the data and associated files. C. Filename: bts_NTAD_Counties_README_20250529.txt Short description: The README.txt file that includes human-readable information about the data, variable definitions, contact information, and other contextual information. The file you are reading now. 2. File List for the Counties_NTAD1995_Present.zip and Counties_Political_NTAD1995_NTAD2015 collections. A. Filename: NTADXXXX_SHP_Final_Counties_XXXX.zip, NTADXXXX_SHP_Final_Counties_Political_XXXX.zip or NTADXXXX_GDB_Final_Counties_XXXX_XX_XX.zip Short description: Compressed file folders containing the geospatial data for Counties 1995-Present dataset. File folders are classified by NTAD publication year and data vintage year respectively. 3a. File List for the NTADXXXX_SHP_Final_Counties_XXXX.zip, NTADXXXX_SHP_Final_Counties_Political_XXXX.zip collection. A. Filename: county.shp Short description: A shapefile containing the geospatial data for Counties 1995-Present dataset. This includes associated files with extensions .prj, .dbf, .sbn, .sbx, .shx. B. Filename: county.met or county.txt, county.htm, and county.shp.xml Short description: Text files containing key metadata and documentation information such as methodology, procedures, data dictionary, etc. 3b. File List for the NTADXXXX_GDB_Final_Counties_XXXX_XX_XX.zip collection A. Filename: NTADXXXX_GDB_Final_Counties_XXXX_XX_XX.gdb.zip Short description: A file geodatabase containing the geospatial data for Counties 1995-Present dataset. Geodatabase (GDB) folders contain all the necessary components to view and otherwise interact with their data. B. Filename: Counties.xml Short description: Text files containing key metadata and documentation information such as methodology, procedures, etc. C. Filename: Counties.xlsx Short description: Excel spreadsheet containing the dataset's data dictionary. ---------------------------------------------------------------- D. METHODOLOGICAL INFORMATION ---------------------------------------------------------------- 1. Description of methods used for collection/generation of data: TIGER/Line Shapefiles are extracted from the Census MAF/TIGER database by nation, state, county, and entity. Census MAF/TIGER data for all of the aforementioned geographic entities are then distributed among the shapefiles each containing attributes for line, polygon, or landmark geographic data. 2. Instrument- or software-specific information needed to interpret the data: The data and documentation files can be opened with Esri ArcMap and any GIS software package. ---------------------------------------------------------------- E. DATA-SPECIFIC INFORMATION ---------------------------------------------------------------- 1. Counties data table There are no planned updates to this dataset. Dataset Manager is contacted to verify changes to data resulting in NTAD update. The metadata is updated in the same manner. For the most recent data, please visit the NTAD catalog at https://doi.org/10.21949/1522038 A. Number of variables (columns): The data dictionary found in (PDF documentation) provides definitions for the variables B. Data Dictionary/Variable List: Because of the large number of variables, please refer to the Data Dictionary found within the file Counties.txt for names, definitions, and formats of variables. C. Missing data codes: None ---------------------------------------------------------------- F. UPDATE LOG ---------------------------------------------------------------- This bts_Counties_20250529_README.txt file was originally created on 2021-03-12 by Dominic Menegus, Geographer, dominic.menegus@dot.gov [Note changes or update to the readme.txt file, e.g.:] 2021-03-12: Original file created 2025-05-29: Revised document, including data descriptions and file organization.