U.S. CENSUS BUREAU TIGER/Line 2003
Census TIGER(R) and TIGER/Line(R) are registered trademarks of the
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Some legal boundaries and names are those reported to the U.S. Census
Bureau to be legally in effect on January 1, 2000 (Census 2000 geographic
areas) while others are updated and legally in effect as of the latest
Boundary and Annexation Survey (BAS) (current geographic areas). The
current boundaries represented in the 2003 TIGER/Line files are those
reported to the Census Bureau by April 1, 2003 as being in effect as of
January 1, 2003. The boundary information in the TIGER/Line files for
both legal and statistical entities are for Census Bureau 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.
WHAT ARE TIGER/LINE FILES
The TIGER/Line files were created from the Census Bureau's TIGER
(Topologically Integrated Geographic Encoding and Referencing) database
of selected geographic and cartographic information. TIGER was
developed at the Census Bureau to support the mapping and related
geographic activities required by the decennial and economic censuses
and sample survey programs. TIGER/Line files are made available to the
public and are typically used by people to provide the digital map base
for their Geographic Information System or mapping software.
WHAT'S NEW - KEY CHANGES
The 2003 TIGER/Line files include files for all counties and
statistically equivalent entities in the United States as well as
files for Puerto Rico and the Island Areas. The 2003 TIGER/Line
files are released by county or statistically equivalent entity
based on the current boundaries in effect as of January 1, 2003 as
reported to the Census Bureau by April 1, 2003. Since Census
2000 there have been changes in the universe of counties or
statistically equivalent entities. In Colorado, Broomfield County
was created from parts of Adams, Boulder, Jefferson, and Weld Counties.
This change has resulted in the creation of a separate TIGER/Line file
for Broomfield County, Colorado. In Virginia, the independent city of
Clifton Forge changed its status to become Clifton Forge town and is
now part of Alleghany County, Virginia; it appears in the Alleghany
County, Virginia TIGER/Line file. Beginning with the 2002 TIGER/Line
files, the Census Bureau no longer produces a TIGER/Line file for
the Midway Islands.
The 2003 TIGER/Line files include the new Record Type E which did not
appear in the 2002 TIGER/Line files. Record Type E contains the
geographic entity codes reflecting the boundaries of the 2002 Economic
Census geographic entities.
In 2002 the U.S. Census Bureau began a multi-year project, the MAF/TIGER
Accuracy Improvement Project (MTAIP), to correct and update the spatial
accuracy of the TIGER database. A portion of the nation's counties or
statistically equivalent entities will be updated each year until all
counties are completed in 2008. While MTAIP was underway before the
creation of the 2003 TIGER/Line files, no counties were through the
MTAIP process at the time the benchmarks used to create the 2003
TIGER/Lines were created. The 2003 TIGER/Line files for 124 counties
or statistically equivalent entities contain improved street feature
coordinates from pre-MTAIP coordinate improvement projects. Twenty of
these counties or statistical equivalent entities with improved street
feature coordinates appeared in the 2002 TIGER/Line files.
The Census Bureau is including county based Federal Geographic Data Committee
(FGDC) compliant metadata for the first time as part of the compressed
2003 TIGER/Line files. More information about the metadata is found
below under the heading "METADATA."
To avoid one of the major difficulties data users had last decade with
the mixing of "current" state and county codes with decennial census
tract and block numbers which are uniquely identified only by the
decennial census state and county codes, the U.S. Census Bureau is
continuing to provide Census 2000 codes on Record Type 1 even though
the distribution unit for the post-Census 2000 TIGER/Line files is
current county or statistically equivalent entity. Since some county
or statistically equivalent entity boundaries have changed since
Census 2000, the current boundaries may not match those used in
Census 2000. Thus it is possible to find some territory that was in
County A in the Census 2000 versions of the TIGER/Line files in the
post-Census 2000 TIGER/Line file for County B.
In counties or statistically equivalent entities that have gained
territory, it is possible to have a complete chain that is a current
county boundary and has the SIDE1 flag set, but has the same state
and county codes on both sides of the complete chain. This occurs
because a polygon that was, for example, in the Census 2000 TIGER/Line
file for County A now is in the post-Census 2000 TIGER/Line file for
County B. Since Record Type 1 displays the Census 2000 geography,
the state and county code for County A (the county or statistically
equivalent entity the lost territory) appears on this complete chain
even though it currently is part of County B. The other side of this
complete chain is in an adjacent TIGER/Line file and the U.S. Census
Bureau appends the current state and county code of the adjacent county
(County A) to this complete chain. The result is a complete chain
that is a current county boundary yet has the same state and county
codes on both sides of the complete chain.
TIGER/LINE AND ACCOMPANYING FILES
To improve the ability of data users to merge multiple counties, the
Census Bureau has added the state and county codes to those Record Type
1 records for the adjacent county (these are the Record Type 1 records
that have the single-sided segment flag set, and until the 2002 version,
all the data elements for the side of the record "outside" the county
were blank). The Census Bureau also is making the TLIDs and TZIDs
for these records the same. Thus the county boundary segments and
zero-cells in adjacent counties will now have the same TLID and TZID.
The data for each county (or statistically equivalent entity) is stored
in a single compressed file that, when decompressed, results in up to
19 separate files representing each of the TIGER/Line record types that
exist for that county. Some counties did not require all of the 19
record types and therefore will have less than 19 files. If the types
of data contained in record types 4, 6, 7, 8, B and Z are not
appropriate for a given county then the files for those record types
will NOT be included. New Record Type U does not appear in the
2003 TIGER/Line files. The name of each of these files uses a
modification of the above convention (TGRssccc.RTx) where "x" is the
Record Type. The data in these files is in a standard ASCII format. The
Census Bureau does NOT release the TIGER/Line data or an extract of the
internal Census TIGER database in vendor-specific GIS/mapping software
Information on the content of each record type can be found in Chapter
6 of the TIGER/Line documentation. Information on decompressing the
data files is found below under the heading "DATA COMPRESSION".
The files use the TIGER/Line record formats as described in the
accompanying documentation. When decompressed they are fixed length
ASCII with record separators (carriage return, line feed).
County-based Federal Geographic Data Committee (FGDC) compliant metadata
is included as part of each compressed TIGER/Line file. The metadata
file has the name TGRssccc.met, where the "ss" is the state FIPS
code and "ccc" is the county FIPS code.
The TIGER/Line data on this disk have been compressed into an archive
file to save space and reduce the number of disks required for the data
and to facilitate downloading from the Internet. If the files were not
compressed it would require over 40 CD-ROM disks to hold the data
needed to cover the entire United States. They are compressed into the
widely used zip format. Use software compatible with PKWARE's PKZIP(R)
to decompress these files; software applications to decompress files in
this format are widely available.
TIGER ZERO-CELL ID (TZID)
Because the 2002 TIGER/Line files were the first version of the
TIGER/Line files to contain the permanent zero-cell identification
number (TZID), we expect there to be some possible differences between
the TZIDs in the 2002 and the 2003 TIGER/Line files. The Census Bureau
expects the TZIDs to be stable in the 2003 and later versions of the
TIGER/Line files. The differences will mainly appear in the 20 counties
with improved street feature coordinates in the 2002 TIGER/Line files
and possibly their adjacent counties.
RANGE OF TIGER/LINE IDENTIFICATION NUMBERS (TLIDS) IN RECORD TYPE R
Record Type H contains the range of unique complete chain record numbers
assigned to a census file. In counties with changes to their county
boundaries after January 1, 2000, the complete range of TLIDs within the
current county boundary do not appear in Record Type R of the 2003
TIGER/Line file for that county. Users will need to reference Record
Type R from the adjoining county to identify the potential range of
unique complete chain record numbers.
ADDRESS ANOMALIES IN PUERTO RICO
The TIGER/Line files contain some address range coverage for Puerto
Rico. However, use of this information for geocoding purposes may be
problematic and the data user should proceed with caution. These
address ranges are preliminary attempts at using Puerto Rico address
ranges in Census Bureau files. Due to the lack of software or
resources to handle some of the more unique aspects of addressing in
Puerto Rico, the address ranges were entered without the standard edits
and quality checks used in other parts of the United States.
Improvements in software and address standardization for Puerto Rico
are expected in the future. At present, there are inconsistencies,
overlaps, and duplication of address ranges. Address ranges may lack
alpha character prefixes or have hyphenated prefixes. The files also
lack the community names used in a four-line address that the U.S.
Postal Service requires to avoid duplicate addresses. Errors in the
reference files, and other factors may limit the usefulness of this
product for geocoding purposes.
ROAD FEATURE ANOMALIES
The Census Bureau extracts TIGER/Line files from the TIGER database
which is continually updated. During the clerical update process for
some Census 2000 operations errors caused anomalies to be introduced
into some chains represented in Record Types 1 and 2. For these cases
road features may appear in the 2003 TIGER/Line files unconnected to
other road features (so-called floating features) or severely skewed in
relation to surrounding line features of any type. We correct these
errors as we find them, however, it is likely that some still exist.
Another road feature anomaly is the sporadic occurrence of road
segments with a misclassified Census Feature Class Code (CFCC). The
result is that complete chains for the affected road features will have
segments with different CFCC values assigned erroneously. This problem
could affect applications that use the CFCC values for network
analysis, routing, or for assigning symbology to a feature when
creating a map. We believe that these errors were introduced
inadvertently during an updating operation to edit address range
information on new as well as existing records. We are continuing to
correct these as they are discovered.