[Federal Register Volume 83, Number 219 (Tuesday, November 13, 2018)]
[Notices]
[Pages 56277-56284]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2018-24567]
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DEPARTMENT OF COMMERCE
Bureau of the Census
[Docket Number 180927898-8898-01]
Census Tracts for the 2020 Census--Final Criteria
AGENCY: Bureau of the Census, Commerce.
ACTION: Notice of final criteria and program implementation.
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SUMMARY: Census tracts are relatively permanent small-area geographic
divisions of a county or statistically equivalent entity defined for
the tabulation and presentation of data from the decennial census and
selected other statistical programs. The Census Bureau is publishing
this notice in the Federal Register to announce final criteria for
defining census tracts for the 2020 Census. Census tracts defined by
these criteria will also be used to tabulate and publish estimates from
the American Community Survey (ACS) and potentially data from other
Bureau of the Census (Census Bureau) censuses and surveys. In addition
to census tracts, the Participant Statistical Areas Program (PSAP)
encompasses the review and update of census block groups, census
designated places, and census county divisions.
DATES: This notice's final criteria will be applicable on December 13,
2018.
FOR FURTHER INFORMATION CONTACT: Requests for additional information on
this proposed program should be directed to Vincent Osier at the
Geographic Standards, Criteria, and Quality Branch, Geography Division,
U.S. Census Bureau, via email at [email protected] or telephone
at 301-763-3056.
SUPPLEMENTARY INFORMATION:
Background
Census tracts are relatively permanent small-area geographic
divisions of a county or statistically equivalent entity \1\ defined
for the tabulation and presentation of data from the decennial census
and selected other statistical programs. The Census Bureau is
publishing this notice in the Federal Register to announce final
criteria for defining census tracts for the 2020 Census. Census tracts
defined by these criteria will also be used to tabulate and publish
estimates from the American Community Survey (ACS) \2\ and potentially
data from other Census Bureau censuses and surveys.
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\1\ For the Census Bureau's purposes, the term ``county''
includes parishes in Louisiana; boroughs, city and boroughs,
municipalities, and census areas in Alaska; independent cities in
Maryland, Missouri, Nevada, and Virginia; districts and islands in
American Samoa; districts in the U.S. Virgin Islands; municipalities
in the Commonwealth of the Northern Mariana Islands; municipios in
Puerto Rico; and the areas constituting the District of Columbia and
Guam. This notice will refer to all these entities collectively as
``counties''.
\2\ The ACS is conducted in the United States and in Puerto
Rico. In Puerto Rico the survey is called the Puerto Rico Community
Survey. For ease of discussion, throughout this document the term
ACS is used to represent the surveys conducted in the United States
and in Puerto Rico.
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In addition to providing final criteria for census tracts, this
notice contains a summary of comments received in response to proposed
criteria published in the Federal Register on February 15, 2018 (83 FR
6941) as well as the Census Bureau's response to those comments. After
publication of final criteria in the Federal Register, the Census
Bureau will offer designated governments or organizations an
opportunity to review and, if necessary, suggest updates to the
boundaries and attributes of the census tracts in their geographic area
through the Participant Statistical Areas Program (PSAP). The program
also encompasses the review and update of census block groups, census
designated places, and census county divisions.
I. History of Census Tracts
In 1905, Dr. Walter Laidlaw originated the concept of permanent,
small geographic areas as a framework for studying change from one
decennial census to another in neighborhoods within New York City. For
the 1910 Census, eight cities--New York, Baltimore, Boston, Chicago,
Cleveland, Philadelphia, Pittsburgh, and St. Louis--delineated census
tracts (then termed ``districts'') for the first time. No additional
jurisdictions delineated census tracts until just prior to the 1930
Census, when an additional ten cities chose to do so. The increased
interest in census tracts for the 1930 Census is attributed to the
promotional efforts of Howard Whipple Green, who was a statistician in
Cleveland, Ohio, and later the chairman of the American Statistical
Association's Committee on Census Enumeration Areas. For more than
twenty-five years, Mr. Green strongly encouraged local citizens, via
committees, to establish census tracts
[[Page 56278]]
and other census statistical geographic areas. The committees created
by local citizens were known as Census Tract Committees, later called
Census Statistical Areas Committees.
After 1930, the Census Bureau saw the need to standardize the
delineation, review, and updating of census tracts and published the
first set of census tract criteria in 1934. The goal of the criteria
has remained unchanged; they assure comparability and data reliability
through the standardization of the population thresholds for census
tracts, as well as requiring that tracts' boundaries follow specific
types of geographic features that do not change frequently. The Census
Bureau began publishing census tract data as part of its standard
tabulations beginning with the 1940 Census. Prior to that time, census
tract data were published as special tabulations.
For the 1940 Census, the Census Bureau began publishing census
block \3\ data for all cities with 50,000 or more people. Census block
numbers were assigned, where possible, by census tract, but for those
cities that had not yet delineated census tracts, ``block areas,''
called ``block numbering areas'' (BNAs) in later censuses, were created
to assign census block numbers.
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\3\ Census blocks are statistical areas bounded by visible
features, such as streets, roads, streams, and railroad tracks, and
by non-visible boundaries, such as selected property lines and city,
township, school district, and county limits and short line-of-sight
extensions of streets and roads. Census blocks cover the entire
territory of the United States, Puerto Rico, and the Island Areas.
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Starting with the 1960 Census, the Census Bureau assumed a greater
role in promoting and coordinating the delineation, review, and update
of census tracts. For the 1980 Census, criteria for BNAs were changed
to make them more comparable in size and shape to census tracts. For
the 1990 Census, all counties contained either census tracts or BNAs.
Census 2000 was the first decade in which census tracts were
defined in all counties. In addition, the Census Bureau increased the
number of geographic areas whose boundaries could be used as census
tract boundaries. It also allowed tribal governments of federally
recognized American Indian tribes with a reservation and/or off-
reservation trust lands to delineate tracts without regard to state
and/or county boundaries, provided the tribe had a 1990 Census
population of at least 1,000.
For the 2010 Census, the Census Bureau adopted changes to census
tract criteria that recognized their utility as a framework of small
geographic areas for presenting and analyzing statistical and other
data for a variety of communities, settlement patterns, and landscapes.
The Census Bureau augmented its minimum, maximum, and optimum
population threshold with housing unit thresholds for use in defining
census tracts for seasonal communities that have no or low population
on census day (April 1). The Census Bureau formalized criteria for
census tracts defined for employment centers, airports, parks, large
water bodies, and other special land uses that had been permitted in
previous decades, but never specified within the criteria. The Census
Bureau also established tribal census tracts as a geographic framework
defined within federally recognized American Indian reservations and
off-reservation trust lands that is fully separate from the standard
census tracts defined within counties.
II. Summary of Comments Received in Response to the Proposed Criteria
The Federal Register published on February 15, 2018 (83 FR 6941)
requested comment on the proposed census tract criteria for the 2020
Census. The proposed criteria were unchanged from the final criteria
adopted for the 2010 Census.
The Census Bureau received comments from 16 individuals or groups
of individuals on topics related to (1) use of non-visible political
boundaries when defining census tracts; (2) use of employment data to
define census tracts encompassing areas with substantial amounts of
commercial, industrial, or other non-residential activity for the
purpose of transportation planning; (3) maintaining historical
comparability; and (4) accounting for statistical data reliability and
quality when developing census tract criteria and defining individual
census tracts. Commenters represented state and local government
agencies, regional planning organizations and councils of governments,
state data centers, non-governmental organizations, and academic
researchers. Comments received by the Census Bureau are summarized
below, as well as the Census Bureau's response to these comments.
1. Using Non-Visible Minor Civil Division Boundaries in Michigan as
Census Tract Boundaries
The Census Bureau received three comments from individuals in
Michigan noting that non-visible minor civil division (MCD) boundaries
in Michigan should be permitted to be census tract boundaries for the
2020 Census as was the case in the past. The commenters correctly noted
that in Table 1, Acceptable Minor Civil Division and Incorporated Place
Boundaries, the proposed criteria were in error with regard to
Michigan. The Census Bureau has corrected the table in the final
criteria.
2. Defining Census Tracts on the Basis of Employment and Jobs
The Census Bureau received 14 comments related to defining census
tracts encompassing areas with concentrations of employment and jobs or
other types of non-residential uses to improve the utility of census
tracts for transportation and journey-to-work analysis and planning.
Eleven commenters suggested adoption of a minimum threshold of 1,200
workers/jobs (and no maximum or optimum thresholds) to be applied as an
alternative to the existing minimum population or housing unit
threshold or in combination with population or housing unit thresholds.
One commenter supported the use of worker/job counts when defining
census tracts, but did not specify a minimum threshold. Two commenters
expressed support for modifying criteria for special use census tracts
primarily to improve identification of census tracts encompassing areas
with concentrations of employment. One commenter noted that applying
employment thresholds was not necessary as the sample design for the
American Community Survey (which is the source for much of the
demographic data used in journey-to-work analysis) focused on
residential population concentrations rather than employment
concentrations. This commenter suggested that changes to the special
use census tract land area criteria could achieve the result desired by
commenters proposing employment thresholds and could provide greater
flexibility when defining census tracts.
Based on consideration of the comments received on this topic and
further discussion with stakeholders in the transportation community,
the Census Bureau will change its criteria for defining special use
census tracts to no longer specify minimum land area requirements.
Special use census tracts should be comparable in land area size to
surrounding census tracts to assure data reliability and quality when
reporting on workplace-related data and to avoid data disclosure
issues. The Census Bureau also recommends that, when defining special
use census tracts encompassing employment centers and areas with
concentrations of jobs, PSAP participants should strive for a minimum
threshold of 1,200 workers/jobs.
[[Page 56279]]
3. Maintaining Historical Comparability
One commenter noted the importance of maintaining historical
boundaries of census tracts for chronicling change in the
sociodemographic characteristics of neighborhoods. The commenter noted
that, while adherence to specified population thresholds (particularly
the optimum and maximum population thresholds, which factor in
decisions to split census tracts) is an important characteristic of
census tracts, comparability over time also is a critical
characteristic. Further, allowing census tracts to exceed the optimum
and maximum thresholds will help mitigate issues related to the large
sampling error associated with small geographic areas. The commenter
suggested that by leaving census tract boundaries unchanged (i.e., by
not splitting census tracts), local governments will be able to
aggregate census tracts more easily to the neighborhood level, allowing
for comparability over time as well as more reliable data. The
commenter further suggested that if census tracts must be merged in
order to meet the minimum population threshold, then an effort should
be made to align the boundaries for block groups within the new census
tract with the boundaries of the former census tracts.
The Census Bureau agrees with the sentiments expressed by this
commenter and will continue to allow individual PSAP participants to
avoid splitting census tracts if they are more concerned about
historical comparability or statistical data reliability or both. We
also agree with the suggestion to align block group boundaries with the
boundaries of former census tracts in those instances in which census
tracts have been merged and will update the final criteria accordingly.
4. Data Quality as an Explicit Criterion for Census Tracts
One comment, submitted by a team of researchers, centered around
the quality and reliability of statistical data for census tracts and
other small geographic areas. Their concern was that the current
methodology for updating and defining census tracts, with its focus on
maintaining historical comparability as well as adherence to the
optimum threshold of 4,000 persons, results in a framework of small
geographic areas that may not meet current analytical and policy
development needs for statistically reliable data. Similar to the
sentiment expressed by the comment discussed above, this group of
commenters suggested that in some places and contexts, the population
size of census tracts should be allowed to increase beyond the maximum
threshold, adding that these larger units would provide higher quality
data because they would contain more responses from sample-based
surveys. However, in their suggestion regarding adoption of explicit
statistical data quality criteria, the commenters are proposing a
fundamental change in the process for defining census tracts for data
dissemination purposes; that is, if a census tract does not achieve the
quality criterion for a given data release, it would be combined with
an adjacent tract. The commenters suggest that through this
combination, the margins of error on the estimates will be reduced, and
data users will be able to obtain a more reliable estimate for a new
larger ``census tract'' (encompassing multiple ``sub-tracts'').
While this is an intriguing idea, the Census Bureau cannot
implement it at this time. Through the 2020 PSAP, the Census Bureau
works with participants to update census tract boundaries prior to the
2020 Census to define a stable geographic framework for tabulating and
presenting decennial census and ACS data. As we understand it, the
commenters' proposal would result in a framework of ``preliminary''
census tracts that would be combined, as necessary, to meet statistical
data reliability criteria after data have been tabulated, but prior to
final release. The Census Bureau needs more time than is available
prior to the start of the 2020 PSAP delineation process to research
this proposal and consider any potential data tabulation, data
disclosure, and analytical implications, particularly if census tracts
were combined in different ways depending on the specific mix of
variables presented in a particular data tabulation.
III. General Principles and Criteria for Census Tracts for the 2020
Census
A. General Principles
1. The primary goal of the census tract is to provide a set of
nationally consistent small, statistical geographic units, with stable
boundaries, that facilitate analysis of data across time. A century of
census tract use, along with ACS and the averaging of sample data for
tracts over a five-year span, has shown that continuity and
comparability in tracts and their boundaries over time are of
considerable importance to data users. Pursuant to this goal, the
Census Bureau requests that where a census tract must be updated, for
example to meet the minimum or maximum population or housing unit
thresholds, that the outer boundaries of the tract not be changed, but
rather that a tract be split into two or more tracts, or merged with an
adjacent tract. The Census Bureau discourages changes to tract
boundaries (that is, ``retracting''), except in specified
circumstances, which the Census Bureau will review on a case-by-case
basis.
2. In order to ensure a minimal level of reliability in sample data
and minimize potential disclosures of sensitive information, a census
tract should contain at least 1,200 people or at least 480 housing
units at minimum, and 8,000 people or 3,200 housing units at maximum.
PSAP participants should aim to create census tracts that meet the
optimal population of 4,000 or 1,600 housing units and maintain the
minimum thresholds unless it is flagged as a special use tract
(discussed below), or is coextensive with a county with fewer than
1,200 people. The housing unit criterion is used to accommodate areas
that are occupied seasonally and may otherwise show a discrepancy
between decennial and ACS figures.\4\
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\4\ ``Occupied seasonally'' refers to seasonal communities in
which residents often are not present on the date of the decennial
census, but will be present at other times of the year and for which
estimates may be reflected in the ACS. The ACS is designed to
produce local area data as of a 12-month period estimate (or an
average).
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3. The Census Bureau recognizes that there are significant
geographic areas that are characterized by unique populations (e.g.,
prisons or universities) or not characterized by residential
populations at all (e.g., National Parks, large bodies of water, or
employment centers) which local participants may wish to exclude from
populated census tracts for either analytical or cartographic purposes.
These areas may be designated as special use census tracts to
distinguish them from standard populated census tracts. Special land
and/or water use census tracts are not required, but if delineated they
must be designated as a specific type of special use (discussed below),
have an official name, ideally have no residential population or
housing units or at least meet all minimum population or housing
thresholds mention above, and must not create noncontiguous census
tracts. While there are no longer minimum land area measurement
thresholds for special use tracts in urban or rural areas, such census
tracts should be comparable in size to surrounding census tracts,
particularly if defined to encompass employment centers or other areas
containing a greater concentration of jobs than residents. The Census
Bureau recognizes that some special use areas not intended for
residential
[[Page 56280]]
population, such as parks, may contain some minimal population, such as
caretakers or those experiencing homelessness. Since the primary
purpose of census tracts is to help provide high-quality statistical
data about the population, the participant and the Census Bureau must
decide if a special use tract would be useful in such a situation.
4. To facilitate the analysis of data for American Indian tribes,
and to recognize their unique governmental status, program participants
are encouraged to merge, split, or redefine census tracts to avoid
unnecessarily splitting American Indian reservations (AIRs) and off-
reservation trust lands (ORTLs). Each contiguous AIR and/or ORTL should
be included, along with any necessary territory outside the AIR and/or
ORTL, within a single census tract or as few census tracts as possible
for the 2020 Census. This is the only situation in which retracting is
encouraged (Figure 1).
[GRAPHIC] [TIFF OMITTED] TN13NO18.096
B. Criteria
The criteria herein apply to the United States, including federally
recognized AIRs and ORTLs, Puerto Rico, and the Island Areas.\5\ The
Census Bureau may modify and, if necessary, reject any proposals for
census tracts that do not meet the published criteria. In addition, the
Census Bureau reserves the right to modify the boundaries and
attributes of census tracts as needed to meet the published criteria
and/or maintain geographic relationships before or after the final
tabulation geography is set for the 2020 Census.
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\5\ For Census Bureau purposes, the United States typically
refers to only the fifty states and the District of Columbia, and
does not include the U.S. territories (Puerto Rico, the Island
Areas, and the U.S. Minor Outlying Islands). The Island Areas
includes American Samoa, the Commonwealth of the Northern Mariana
Islands, Guam, and the U.S. Virgin Islands. The U.S. Minor Outlying
Islands are an aggregation of nine U.S. territories: Baker Island,
Howland Island, Jarvis Island, Johnston Atoll, Kingman Reef, Midway
Islands, Navassa Island, Palmyra Atoll, and Wake Island.
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The Census Bureau sets forth the following criteria for use in
reviewing, updating, and delineating 2020 Census tracts:
5. Census tracts must not cross county or state boundaries.
This criterion takes precedence over all other criteria or
requirements (except for tribal tracts on federally recognized AIRs
and/or ORTLs).
6. Census tracts must cover the entire land and water area of a
county.
7. Census tracts must comprise a reasonably compact and contiguous
land area.
Noncontiguous boundaries are permitted only where a contiguous area
or inaccessible area would not meet population or housing unit count
requirements for a separate census tract, in which case the
noncontiguous or inaccessible area must be combined within an adjacent
or proximate tract. For example, an island that does not meet the
minimum population threshold for recognition as a separate census tract
should be combined with other proximate land to form a single,
contiguous census tract. Each case will be reviewed and accepted at the
Census Bureau's discretion.
8. Census tract boundaries should follow visible and identifiable
features.
To make the location of census tract boundaries less ambiguous,
wherever possible, tract boundaries should follow significant, visible,
easily identifiable features. The use of visible features facilitates
the location and identification of census tract boundaries in the
field, both on the ground and in imagery. The selection of permanent
physical features also increases the stability of the boundaries over
time, as the locations of many visible features in the landscape tend
to change infrequently. If census tract boundaries are changed, they
should not be moved from a more
[[Page 56281]]
significant feature (e.g., a highway or a major river) to a less
significant feature (e.g., a neighborhood road or a small tributary
stream). By definition, state and county boundaries must be used as
census tract boundaries. The Census Bureau also permits the use of
incorporated place and minor civil division (MCD) boundaries in states
where those boundaries tend to remain unchanged over time (see Table
1).
The following features are preferred as census tract boundaries for
the 2020 Census:
a. State and county boundaries must always be census tract
boundaries. This criterion takes precedence over all other boundary
criteria or requirements.
b. AIR and ORTL boundaries.
c. Visible, perennial, stable, relatively permanent natural and
constructed features, such as roads, shorelines, rivers, perennial
streams and canals, railroad tracks, or above-ground high-tension power
lines.
d. Boundaries of legal and administrative entities in selected
states. Table 1 identifies by state which MCD and incorporated place
boundaries may be used as census tract boundaries.
e. Additionally, the following legally defined, administrative
boundaries would be permitted as census tract boundaries:
i. Barrio, barrio-pueblo, and sub-barrio boundaries in Puerto Rico;
ii. Census subdistrict and estate boundaries in the U.S. Virgin
Islands;
iii. County and island boundaries (both MCD equivalents) in
American Samoa;
iv. Election district boundaries in Guam;
v. Municipal district boundaries in the Commonwealth of the
Northern Mariana Islands; and,
vi. Alaska Native Regional Corporation boundaries in Alaska, at the
discretion of the Census Bureau, insofar as such boundaries are
unambiguous for allocating living quarters as part of 2020 Census
activities.
f. The boundaries of large parks, forests, airports,
penitentiaries/prisons, and/or military installations, provided the
boundaries are clearly marked or easily recognized in the field, in
imagery, and on the ground.
g. When acceptable visible and governmental boundary features are
not available for use as census tract boundaries, the Census Bureau
may, at its discretion, approve other nonstandard visible features,
such as major ridgelines, above-ground pipelines, intermittent streams,
or fence lines. The Census Bureau may also accept, on a case-by-case
basis, relatively short stretches of boundaries of selected nonstandard
and potentially nonvisible features, such as cadastral and parcel
boundaries or the straight-line extensions or other lines-of-sight
between acceptable visible features.
Table 1--Acceptable Minor Civil Division (MCD) and Incorporated Place Boundaries
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Boundaries of
MCDs not co-
incident with All Only conjoint
All MCD the boundaries incorporated incorporated
State boundaries of incorporated place place
places that boundaries boundaries
themselves are
MCDs
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Alabama..................................... ............... ............... ............... X
Alaska...................................... ............... ............... ............... X
Arizona..................................... ............... ............... ............... X
Arkansas.................................... ............... ............... ............... X
California.................................. ............... ............... ............... X
Colorado.................................... ............... ............... ............... X
Connecticut................................. X ............... X ...............
Delaware.................................... ............... ............... ............... X
Florida..................................... ............... ............... ............... X
Georgia..................................... ............... ............... ............... X
Hawaii...................................... ............... ............... ............... ...............
Idaho....................................... ............... ............... ............... X
Illinois.................................... ............... X \a\ ............... X
Indiana..................................... X ............... ............... X
Iowa........................................ ............... X ............... X
Kansas...................................... ............... X ............... X
Kentucky.................................... ............... ............... ............... X
Louisiana................................... ............... ............... ............... X
Maine....................................... X ............... X ...............
Maryland.................................... ............... ............... ............... X
Massachusetts............................... X ............... X ...............
Michigan.................................... ............... X ............... X
Minnesota................................... ............... X ............... X
Mississippi................................. ............... ............... ............... X
Missouri.................................... ............... X \b\ ............... X
Montana..................................... ............... ............... ............... X
Nebraska.................................... ............... X \a\ ............... X
Nevada...................................... ............... ............... ............... X
New Hampshire............................... X ............... X ...............
New Jersey.................................. X ............... X ...............
New Mexico.................................. ............... ............... ............... X
New York.................................... X ............... X ...............
North Carolina.............................. ............... ............... ............... X
North Dakota................................ ............... X ............... X
Ohio........................................ ............... X ............... X
Oklahoma.................................... ............... ............... ............... X
Oregon...................................... ............... ............... ............... X
[[Page 56282]]
Pennsylvania................................ X ............... X ...............
Rhode Island................................ X ............... X ...............
South Carolina.............................. ............... ............... ............... X
South Dakota................................ ............... X ............... X
Tennessee................................... ............... ............... ............... X
Texas....................................... ............... ............... ............... X
Utah........................................ ............... ............... ............... X
Vermont..................................... X ............... X ...............
Virginia.................................... ............... ............... ............... X
Washington.................................. ............... ............... ............... X
West Virginia............................... ............... ............... ............... X
Wisconsin................................... ............... X ............... X
Wyoming..................................... ............... ............... ............... X
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\a\ Townships only.
\b\ Governmental townships only.
9. Population, Housing Unit, and Area Measurement Thresholds
The following are the population, housing unit, and area
measurement threshold criteria for census tracts (as summarized in
Table 2). The same population and housing unit thresholds apply to all
types of non-special use census tracts, including census tracts
delineated for AIRs and ORTLs, the Island Areas, and encompassing group
quarters, military installations, and institutions.
Table 2--Census Tract Thresholds
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Census tract type Threshold type Optimum Minimum Maximum
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Standard & tribal census tracts. Population 4,000............. 1,200............. 8,000.
threshold. 1,600............. 480............... 3,200.
Housing unit
threshold.
Special use census tracts....... Area measurement.. At least At least At least
comparable in comparable in comparable in
land area size to land area size to land area size to
surrounding surrounding surrounding
census tracts. census tracts. census tracts.
-----------------------------------------------------------
Employment Suggested minimum of 1,200 workers or jobs.
threshold
(suggested).
----------------------------------------------------------------------------------------------------------------
a. 2010 Census population counts should be used in census tract
review in most cases. Housing unit counts should be used for census
tracts in seasonal communities that have little or no population on
Census Day (April 1). Locally produced population and housing unit
estimates can be used when reviewing and updating census tracts,
especially in areas that have experienced considerable growth since the
2010 Census.
b. The housing unit thresholds are based on a national average of
2.5 persons per household. The Census Bureau recognizes that there are
local and regional variations to this average, and will take this into
consideration when reviewing all census tract proposals.
c. Any census tract with a population or housing unit count less
than the minimum threshold should be merged with an adjacent census
tract to form a single tract with at least 1,200 people or at least 480
housing units (Figure 2). The Census Bureau recognizes the complexity
that exists between meeting the optimum population or housing unit
threshold in a census tract and maintaining census tract comparability
over time. For example, if the population or housing unit count based
on 2010 Census data was below the minimum thresholds, but significant
growth has occurred since 2010 or is expected before 2020 for a census
tract, the census tract should not be merged with another census tract.
Supporting evidence may be requested by the Census Bureau. However, if
the census tract's population does not increase as expected and does
not meet either the minimum population or housing unit thresholds for
2020, this may adversely affect the reliability and availability of any
sample estimates for that census tract. For this reason, the Census
Bureau suggests merging the census tract with another adjacent census
tract if there is a possibility that anticipated growth will not be
sufficient to meet minimum thresholds. When merging census tracts, the
Census Bureau suggests retaining the former census tract boundaries as
boundaries for block groups within the newly defined census tract to
facilitate historical analysis.
[[Page 56283]]
[GRAPHIC] [TIFF OMITTED] TN13NO18.097
d. For the 2020 Census, the Census Bureau will allow the
delineation of special use census tracts, but they are not required. A
special use census tract must be designated as a specific use type
(e.g., state park), must have an official name (e.g., Jay Cooke State
Park), have no (or very little) residential population or meet
population or housing unit thresholds, and must not create a
noncontiguous census tract. In some instances, multiple areas can be
combined to form a single special use census tract if the land use or
land management characteristics are similar, such as a special use
census tract comprising an area with a concentration of employment or
adjacent federal and state parks. Any resulting special use census
tract should be at least as large in area as the surrounding standard,
populated census tracts.
10. Identification of Census Tracts
a. A census tract has a basic census tract identifier composed of
no more than four digits and may have a two-digit decimal suffix.
b. The range of acceptable basic census tract identifiers for the
2020 Census is from 1 to 9989 (see 6.c. below for exceptions); special
use census tracts delineated specifically to complete coverage of large
water bodies will be numbered from 9950 to 9989 in each county.
c. Census tracts delineated within or to primarily encompass AIRs
and/or ORTLs should be numbered from 9400 to 9499.
d. Census tract identifiers must be unique within each county.
e. Once used, census tract identifiers cannot be reused in a
subsequent census to reference a completely different area within a
county. If a census tract is split, each portion may keep the same
basic 4-digit identifier, but each portion must be given a unique
suffix. If a census tract that was suffixed for 2010 Census is split,
each portion must be given a new suffix.
f. The range of acceptable census tract suffixes is .01 to .98.
11. Census Tract Types
Table 3 provides a summary of the types of census tracts (with
their respective population, housing unit, and area measurement
thresholds) that the Census Bureau will use for the 2020 Census.
Table 3--Summary of Census Tract Types
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Distinction from Population Housing unit Area measurement
Census tract type standard census tract thresholds thresholds thresholds
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Standard census tract.......... ...................... Optimum: 4,000; Optimum: 1,600; None.
Min: 1,200; Max: Min: 480; Max:
8,000. 3,200.
Tribal census tract............ Tribal census tracts Optimum: 4,000; Optimum: 1,600; None.
are conceptually Min: 1,200; Max: Min: 480; Max:
similar and 8,000. 3,200.
equivalent to census
tracts defined within
the standard state-
county-tract
geographic hierarchy
used for tabulating
and publishing
statistical data.
Special use census tract....... A census tract None (or very None (or very At least
encompassing an little) or little) or comparable in
employment center, within the within the size to
large airport, public standard census standard census surrounding
park, public forest, tract threshold. tract threshold. standard census
or large water body tracts.
with no (or very
little) population or
housing units.
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B. Tribal Census Tracts
Tribal census tracts are statistical geographic entities defined by
the Census Bureau in cooperation with tribal officials to provide
meaningful, relevant, and reliable data for small geographic areas
within the boundaries of federally recognized AIRs and/or ORTLs. As
such, they recognize the unique statistical data needs of federally
recognized American Indian tribes. The delineation of tribal census
tracts allows for an unambiguous presentation of census tract-level
data specific to the federally recognized AIR and/or ORTL without the
imposition of state or county boundaries, which might artificially
separate American Indian populations located within a single AIR and/or
ORTL. To this end, the American
[[Page 56284]]
Indian tribal participant may define tribal census tracts that cross
county or state boundaries, or both. For federally recognized American
Indian tribes with AIRs and/or ORTLs that have more than 2,400
residents, the Census Bureau will offer the tribal government the
opportunity to delineate tribal census tracts and other tribal
statistical geography on their AIR and/or ORTL. For federally
recognized tribes with an AIR and/or ORTL with fewer than 2,400
residents, the Census Bureau will define one tribal census tract
coextensive with the AIR and/or ORTL. Tribal census tracts must be
delineated to meet all other census tract criteria, and must be
identified uniquely to clearly distinguish them from county-based
census tracts. Tribal census tracts are conceptually similar and
equivalent to census tracts defined within the standard state-county-
tract geographic hierarchy used for tabulating and publishing
statistical data.
In order to provide meaningful statistical geographic areas within
the AIR and/or ORTL, as well as make meaningful and reliable data
available for these areas and their populations, tribal census tract
geography is maintained separately from standard county-based census
tracts. This change was first introduced for the 2010 Census, creating
standard, county-based census tracts nationwide and maintaining tribal
census tracts as a completely separate set of geography from standard
census tracts for both geographic and data presentation purposes. The
change eliminated, in part, the reliability and availability data
issues for the tribal census tracts and the derived standard census
tracts that were present in Census 2000. \6\
---------------------------------------------------------------------------
\6\ For Census 2000, tribal tracts were defined for federally
recognized AIRs and/or ORTLs and standard census tracts were
identified by superimposing county and state boundaries onto the
tribal tracts. For Census 2000 products in which data were presented
by state and county, the standard state-county-census tract
hierarchy was maintained, even for territory contained within an AIR
and/or ORTL. In such instances, the state-county portions of a
tribal tract were identified as individual census tracts. These
standard census tracts may not have met the minimum population
thresholds, potentially limiting sample data reliability or
availability for both the tribal tract and the derived standard
census tracts.
---------------------------------------------------------------------------
As with standard census tracts submitted through this program, the
tribal census tracts are submitted to the Census Bureau, and are
subject to review to ensure compliance with the published criteria.
Detailed criteria pertaining to tribal census tracts will be published
in a separate Federal Register notice pertaining to all American Indian
areas, including statistical areas defined through the PSAP.
IV. Definitions of Key Terms
Alaska Native Regional Corporation (ANRC)--A corporate geographic
area established under the Alaska Native Claims Settlement Act (Pub. L.
92-203, 85 Stat. 688 (1971)) to conduct both the business and nonprofit
affairs of Alaska Natives. Twelve ANRCs cover the entire state of
Alaska except for the Annette Island Reserve.
American Indian off-reservation trust land (ORTL)--An area of land
located outside the boundaries of an AIR, whose boundaries are
established by deed, and which are held in trust by the U.S. federal
government for a federally recognized American Indian tribe or members
of that tribe.
American Indian reservation (AIR)--An area of land with boundaries
established by final treaty, statute, executive order, and/or court
order and over which a federally recognized American Indian tribal
government has governmental authority. Along with ``reservation,''
designations such as colonies, communities, pueblos, rancherias, and
reserves apply to AIRs.
Census block--Census blocks are statistical areas bounded by
visible features, such as streets, roads, streams, and railroad tracks,
and by non-visible boundaries, such as selected property lines and
city, township, school district, and county limits and short line-of-
sight extensions of streets and roads. Census blocks cover the entire
territory of the United States, Puerto Rico, and the Island Areas.
Conjoint--A description of a boundary line shared by two adjacent
geographic entities.
Contiguous--A description of areas sharing common boundary lines,
more than a single point, such that the areas, when combined, form a
single piece of territory. Noncontiguous areas form disjoint pieces.
Group quarters--A location where people live or stay, in a group
living arrangement, that is owned or managed by an entity or
organization providing housing and/or services for the residents. This
is not a typical household-type living arrangement. These services may
include custodial or medical care as well as other types of assistance,
and residency is commonly restricted to those receiving these services.
People living in group quarters are usually not related to each other.
Group quarters include such places as college residence halls,
residential treatment centers, skilled nursing facilities, group homes,
military barracks, correctional facilities, and workers' dormitories.
Incorporated place--A type of governmental unit, incorporated under
state law as a city, town (except in New England, New York, and
Wisconsin), borough (except in Alaska and New York), or village,
generally to provide governmental services for a concentration of
people within legally prescribed boundaries.
Minor civil division (MCD)--The primary governmental or
administrative division of a county in 28 states and the Island Areas
having legal boundaries, names, and descriptions. The MCDs represent
many different types of legal entities with a wide variety of
characteristics, powers, and functions depending on the state and type
of MCD. In some states, some or all of the incorporated places also
constitute MCDs.
Nonvisible feature--A map feature that is not visible on the ground
such as a city or county boundary through space, a property line, or
line-of-sight extension of a road.
Retracting--Substantially changing the boundaries of a census tract
so that comparability over time is not maintained.
Special use census tract--Type of census tract that must be
designated as a specific use type (e.g., state park or large lake) and
have an official name (e.g., Jay Cooke State Park or Lake Minnetonka),
should have no (or very little) population or housing units, and must
not create a noncontiguous census tract. If delineated in a densely
populated, urban area, a special use census tract must have an area of
at least one square mile. If delineated completely outside an urban
area, a special use census tract must have an area of at least 10
square miles.
Visible feature--A map feature that can be seen on the ground and
in imagery, such as a road, railroad track, major above-ground
transmission line or pipeline, river, stream, shoreline, fence, sharply
defined mountain ridge, or cliff. A nonstandard visible feature is a
feature that may not be clearly defined on the ground (such as a
ridge), may be seasonal (such as an intermittent stream), or may be
relatively impermanent (such as a fence). The Census Bureau generally
requests verification that nonstandard features used as boundaries for
the PSAP geographic areas pose no problem in their location during
field work.
Dated: October 30, 2018.
Ron S. Jarmin,
Deputy Director, Performing the Non-Exclusive Functions and Duties of
the Director, Bureau of the Census.
[FR Doc. 2018-24567 Filed 11-9-18; 8:45 am]
BILLING CODE 3510-07-P