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This section reviews use of Census 2010/Census 2000 "Census Tract Street Index" (CTSI) files developed by Proximity using the Census 2010 TIGER/Line files and related data. The CTSI files provide a means to associate addresses with a Census 2010 and/or Census 2000 census tract/census block. By assigning the census block (in which the address is located)
The Proximity CTSI software and database can be used to locate census tract/block codes interactively for single addresses or in a batch mode to process an address file. When used in the batch mode, the state, county, tract, block geocodes, and optionally other codes and subject matter data, are appended to the original address record and a new file is created/output.
About Census Tracts/Blocks. Census tracts are geographic areas defined by the Census Bureau and organized as sub-county statistical building blocks. Designed to average 4,000 population, but vary widely. The approximate 65,000 census tracts covering the U.S. wall-to-wall provide a good geographic granularity to meet many needs. Unchanging throughout the decade, census tract boundaries are subject to update for each decennial census though many will remain unchanged for Census 2010.
An illustrative CTSI interactive table is shown below for street segments located in Fairfax County, VA. The CTSI database covers the U.S. wall-to-wall and is available for single counties, county groups or the U.S. There is a row for each named road segment in the county. Not all items in the CTSI base file are shown. The table has been developed through use of several Census 2010 TIGER/Line shapefiles and related files. The table is intended to illustrate the process of associating a tract/block with an address. The actual CTSI application runs on the user Windows-based computer. The next few graphics show an example for looking up one address (6405 16th Street) and maps illustrating the street and related tract/block geography based on Census 2000 and Census 2010 geography. The table can be used to determine the tract/block code for most addresses in the county.
Applications Area -- Google Map
To illustrate how the process works, one address will be located on 16th Street in Fairfax County. The pointer shows street segment in context of satellite imagery view.
Applications Area -- CV with TIGER/Line Shapefiles
Pointer shows street segment in context of view. The segment of interest has Census 2000 (red boundary) block 1010 on one side and block 1012 on the other side; and Census 2010 (blue boundary) block 4017 on one side and block 4018 on the other side. The tract is the same on both sides and the same in Census 2000 and in Census 2010.
Applications Area -- CV with TIGER/Line Shapefiles - Zoom-in
Pointer shows street segment in context of specific census blocks. This zoom-in view shows relationships between Census 2000 and Census 2010 block boundaries more clearly.
See application notes below table.
CTSI Interactive Address to Census Tract/Block Assignment
Uses road/street data for Fairfax County, VA
Usage: click column header to sort; click again to sort other direction.
Column Headers; Item Descriptions
For each road/street segment (typically intersection to intersection)
P1 - prefix direction description component of the feature name
P2 - prefix type description component of the feature name
P3 - prefix qualifier description component of the feature name
NAME - base name -- base name portion of the standardized name
S1 - suffix direction description component of the feature name
S2 - suffix type description component of the feature name
S3 - suffix qualifier description component of the feature name
FULLNAME - concatenation of expanded text for prefix qualifier, prefix direction, prefix type, base name, suffix type, suffix direction, and suffix qualifier (as available) with a space between each expanded text field.
L.FROM - left side from address
L.TO - left side to address
R.FROM - right side from address
R.TO - right side to address
ZIPL - left side ZIP code
ZIPR - right side ZIP code
Segment Left Side
TRACT00L census tract 2000
BLOCK00L census block 2000
TRACT10L census tract 2010
BLOCK10L census block 2010
Segment Right Side
TRACT00R census tract 2000
BLOCK00R census block 2000
TRACT10R census tract 2010
BLOCK10R census block 2010
Table Usage Notes
Road/street records shown in the table are sorted on the name + s3 + p1 + left from address columns.
Click on a column header to sort on that column; click column header again to sort in other direction.
Click ShowAll button to show all areas and restore full set of data view.
Key exact text (street name part) in the Find in Name and click Find in Name button to locate all qualifying segment.
... click ShowAll button between Finds.
The Find operation performs a query on the FULLNAME column.
Proximity develops geodemographic-economic data and analytical tools and helps organizations knit together and use diverse data in a decision-making and analytical framework. We develop custom demographic/economic estimates and projections, develop geographic and geocoded address files, and assist with impact and geospatial analyses. Wide-ranging organizations use our tools (software, data, methodologies) to analyze their own data integrated with other data. Contact Proximity (888-364-7656) with questions about data covered in this section or to discuss custom estimates, projections or analyses for your areas of interest.