The map layers shown under the MARPLOT® Census TIGER/Line Layers grouping were produced from the TIGER/Line 1998 data files. The TIGER/Line files are digital databases of geographic features, such as roads, railroads, rivers, lakes, political boundaries, census statistical boundaries, etc. covering the entire United States. The data base contains information about these features such as their location in latitude and longitude, the name, the type of feature, address ranges for most streets, the geographic relationship to other features, and other related information. They are the public product created from the Census Bureau's TIGER (Topologically Integrated Geographic Encoding and Referencing) database of geographic information. TIGER was developed at the Census Bureau to support the mapping and related geographic activities required by the decennial census and sample survey programs.
TIGER/Line® 1998 Metadata
1990 Census Political and Statistical Boundary Data
To maintain compatibility with the 1990 Census data presented in this product, official boundaries used in the 1990 Census data tabulations are shown in this product excepting congressional districts (105th) and Metropolitan Areas (June 30, 1999). With the exception of Hawaii and the Insular territories, both the TIGER/Line 1998 files and the boundary files are based upon the 1983 North American Datum (NAD 83).
Most of the boundaries shown under the MARPLOT "Census Demographic Layers" were created as selected generalized extracts from the Census Bureau's TIGER geographic database. Because these boundaries are simplified from the original polygons, they do not always exactly overlay the street pattern. See Generalized Boundaries for a fuller discussion of this.
The places, census tracts and block group layers are not generalized and were prepared directly from the TIGER/Line 1998 data files.
1990 AIANA Metadata
105th Congressional Districts Boundary Files Metadata
County Boundary Files Metadata
1999 Metropolitan Areas Boundary Files Metadata
Minor Civil Division (MCD)/Census County Division (CCD) Boundary Files Metadata
State Boundary Files Metadata
For those of you interested in other boundary files, please visit the Cartographic Boundary Files site.
Source: U.S. Census Bureau
Last Revised: Tuesday, 11-Dec-2012 09:45:49 EST