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U.S. Census Bureau

Data Availability for Geographic Areas

March 25, 2008

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HierarchyU.S.

Regions and Divisions

State

County

County Subdivision

Place (or place part)

Census tract

Block group

Block

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Census Regions and Divisions

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Three factors usually affect the search for data

from the Census Bureau:

1. topic (e.g., population)

2. geography (e.g., my state)

3. time period (e.g., most recent year). 

.

Search for Data

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Generally the larger the geographic area, the more topics and time periods you can find.

U.S. level – Extensive data

States and Counties - Substantial data

 Cities (i.e., incorporated places) – Somewhat less data

Small areas (census tracts, block groups, and blocks) -

once a decade after the Census Bureau tabulates the

results of the Population and Housing Census.

In 2010 -  the American Community Survey will allow the Census Bureau to release data more frequently for areas as small as census tracts.

Data Availability

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Examples of Data by Small Geography

Census 2000 • Summary File 1 (100%) Census Tract Blocks - most tabulations

• Summary File 2 (100%) Census Tract

• Summary File 3 (Sample) Census Tract Block Group - most tabulations

• Summary File 4 (Sample) Census Tract

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Examples of Data by Small Geography

Economic Census - 2002• Zipcode level

American Community Survey – 2006• Areas of 65,000+ population

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PUMS

and

PUMAs

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Public Use Microdata Sample

Microdata allow users to prepare their own customized tabulations of most population and housing subjects using specially prepared microdata files.

These files are the actual responses to census questionnaires, but with names or addresses removed and the geography sufficiently broad to protect confidentiality.

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What is a PUMA ?

Public Use Microdata Area

PUMA is a geographic entity for which extracts of the full range of population and housing data collected from a small sample of confidentiality-screened census records are provided.

PUMAs are sub-state areas that can be composed of:

A large single county or groups of counties Large places Groups of census tracts Combination of tract and county and Other variations

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PUMA Delineation

The Census Bureau offered State Data Centers (SDCs) the opportunity to delineate, or coordinate the delineation of, the super-PUMAs and the PUMAs. The SDCs (or their equivalents) in 48 states, the District of Columbia, and Puerto Rico participated in the delineation program.

PUMA codes must be used in conjunction with the 2-digit FIPS state codes.

PUMAs: Minimum population of 100,000 - cannot cross a state line. (5% long-form records sample)

Super PUMAs: Aggregated PUMAs with a minimum population of 400,000 - cannot cross state lines. (1% long-form records sample)

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Public Use Microdata Areas

500

100

600

400

200

300

00100

01000

01100

01300

00900

01800

02200

01200

00200

02100

01400

02300

00400

00700

01600

00500

01500

02300

01700

02500

00600

00300

01900

02000

02400

00800

FAIRFIELD

HARTFORD

NEW LONDON

MIDDLESEX

LITCHFIELD

NEW HAVEN

TOLLANDWINDHAM

1% Public Use Microdata Area (PUMA)

5% Public Use Microdata Area (PUMA)

County Boundary

Sea

COUNTY NAME

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Large Single County - PUMA 00100

Multiple

Counties

PUMAs

00500

00200

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Large City PUMA 00700

Census

Tract

GroupsPUMAs

00802

00803

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Putnam County

+

One census tract in Westchester

County

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Data by PUMAs

Available

Decennial Census

American Community Survey

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Mapping Online

Maps available on www.census.gov

Static

Interactive

Thematic

Reference

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Census 2000 Census Tract Map

Zoom

Pan

Select

Search

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Static Map

Reference Map

Theme Map

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Theme Map

County Business Patterns

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Interactive Census Tract

Reference MapChange Boundaries

Pan

Zoom in

Zoom out

Print

Download

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Static Reference Map

Print

Download

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Reference Map

Use Map to Select a Neighborhood

Data table is selected

Show Result

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New York Regional Census Center

330 W. 34th Street – 13th floor

NY, NY 10001

646-233-2404