• The Precensus files added a “sign” to each latitude
and longitude value to identify the hemisphere in which
it is located — because the TIGER data base covers
territory in 3 of the 4 hemisphere combinations on Earth!
• Most of the other changed items will make the
Precensus and future versions of the TIGER/Line files
conform more to the various Federal Information Pro
cessing Standards (FIPS) conventions that guide the
content of geographic files in the United States.
The Precensus TIGER/Line files are available from the
Data User Services Division of the Census Bureau on
magnetic tape and CD-ROM. They also are available on
magnetic tape from many of the State Data Centers and
some commercial software vendors.
The Census Bureau’s price for the Precensus TIGER/
Line files on magnetic tape is $200 for the first county
ordered in a state, plus $25 for each additional county in
that state ordered at the same time. The price for the
entire set of Precensus TIGER/Line files covering the 50
states plus the District of Columbia is $87,450. If a
customer also wishes to include the files for American
Samoa, Guam, the Northern Mariana Islands, Palau,
Puerto Rico, the Virgin Islands of the United States, and
the other areas comprising the former Trust Territory of
the Pacific Islands, the price is $90,150. The Census
Bureau’s price for the Precensus TIGER/ Line files on
CD-ROM is $250 per disk; the entire set takes 37 disks, so
the cost of the entire United States and all associated
territories on CD-ROM is $9,250.
Future Files
The next version of the TIGER/Line files -- the Initial
Voting District Codes version, which the Census Bureau
expects to complete in October 1990 -- will contain the
street and street name updates found by the 1990 census
field staff -- called enumerators — who have walked
around all the blocks in the United States carrying maps
produced from the TIGER data base. Those enu
merators discovered where the TIGER data base had
errors and marked the corrections on their maps. This
version of the file also will contain the map corrections
that local officials have reported to the Census Bureau
based on their use of the maps for various 1990 census-
related programs.
For the geographic entity user, the Initial Voting
District Codes TIGER/Line files will include the “first
draft” of the geographic codes for the blocks enclosed by
the January 1, 1990 boundaries of the governmental
entities — the official set for the 1990 census. This ver
sion also will include the “first draft” of the codes for the
voting districts reported by the state governments
participating in the 1990 Redistricting Data Program
(LaMacchia, 1989; U.S. Bureau of the Census, 1987; and
U.S. Bureau of the Census, 1989c).
In addition to more current information about features
and geographic entities, the Initial Voting District Codes
TIGER/Line files will include four new record types to
document the point and area landmark information in
the TIGER data base that was not included in the first
two versions of the TIGER/Line files. This added infor
mation will increase the usefulness of the TIGER/Line
files for GIS applications by providing the names for
areal features (polygons) such as lakes, wide rivers,
oceans, major parks, military bases, and so forth.
Because the Initial Voting District Codes version of the
TIGER/Line file is a recent addition to the planned set
and must be prepared during the peak period of
1990 census processing operations, the file will be
available only on magnetic tape and the price for each
file will be slightly higher than the Precensus version:
$215 for the first county in a state and $40 for each
additional county in that state ordered at the same time.
The Census Bureau expects to provide the fourth version
— the 1990 Census TIGER/Line file — on both magnetic
tape and CD-ROM at the same price as the corre
sponding Precensus version. The 1990 Census TIGER/
Line files will be available beginning in January 1991
with the last files released by the end of March 1991. For
more information on the TIGER/Line files, contact the
staff at the address and telephone number shown below.
State and Regional Programs Staff
Data User Services Division
Bureau of the Census
Washington, DC 20233
(301) 763-1580
Software
For most data users, the quickest and easiest way to
start using the TIGER/Line files is to obtain, from a ven
dor, software appropriate for the specific task envisioned
and for the computer hardware available in the office
where the files are to be used. More than 58 vendors -
many of whom served data users in processing the
Census Bureau’s summary tape files and the prede
cessor to the TIGER data base, the GBF/DIME-Files -
tell us they have the capability to manipulate and make
use of the TIGER/Line files. The Census Bureau has
been conducting workshops to inform data users about
the TIGER/Line files and other TIGER Extract products
(LaMacchia and Tomasi, 1990), and to demonstrate
some of the commercial software packages.
The Census Bureau believes that the easy availability of
the files, the low cost of the files, and the large number of
processing systems and GIS packages available com
mercially that use them, provide access to the power of
this new product for nearly every potential user.
Together with the demographic data tapes that will be
available following the 1990 census, and the data prod
ucts available from the 1987 economic and agriculture
censuses of the United States, the public has received a
wonderful return on its investment (U.S. Bureau of the
Census 1989b and 1990b).
SHORTCOMINGS AND UPDATING PLANS
One of the major results of any significant new program
— and the Census Bureau believes that the TIGER
System is one of these - is that people develop expec
tations of the product that far exceed the possible. The
TIGER System has not been an exception. Thus, despite
the tremendous accomplishment of developing this
automated cartographic and geographic data base for
the entire United States and its possessions, along with
all the associated map production and other related
processing software, some people were surprised — and
a few were very disappointed - that it was not perfect.
Shortcomings
Based on reports from a small number of individuals
using the TIGER/Line files and reviewing the Census
Bureau’s maps, there are several categories of discrep
ancies: the file is missing some real streets, it contains
some streets that do not exist, it contains some incorrect
street names and has mislabelled some streets, it is
missing some street names, and it contains some mis
takes in the locations of streets, other features, and geo
graphic entity boundaries for the 1990 census.
The Census Bureau’s original plan was to make any
further corrections required to the features and feature
names in the TIGER data base following the completion
of the 1990 census. While staff knew that the maps
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