Technology Transfer Network / NAAQS
Ozone Implementation
Changes to the Standards for Defining Metropolitan Areas; Notice
Note: EPA no longer updates this information, but it may be useful as a reference or resource.
[Federal Register: August 22, 2000 (Volume 65, Number 163)]
[Notices]
[Page 51059-51077]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr22au00-147]
[[Page 51059]]
-----------------------------------------------------------------------
Part II
Office of Management and Budget
-----------------------------------------------------------------------
Final Report and Recommendations From the Metropolitan Area Standards
Review Committee to the Office of Management and Budget Concerning
Changes to the Standards for Defining Metropolitan Areas; Notice
[[Page 51060]]
-----------------------------------------------------------------------
OFFICE OF MANAGEMENT AND BUDGET
Final Report and Recommendations From the Metropolitan Area
Standards Review Committee to the Office of Management and Budget
Concerning Changes to the Standards for Defining Metropolitan Areas
AGENCY: Executive Office of the President, Office of Management and
Budget (OMB), Office of Information and Regulatory Affairs.
ACTION: Notice and request for comment.
-----------------------------------------------------------------------
SUMMARY: OMB requests comment on the final recommendations it has
received from the Metropolitan Area Standards Review Committee for
changes to OMB's metropolitan area standards. The committee's
recommendations, which are published in their entirety in the appendix
to this Notice, reflect the comprehensive review of the metropolitan
area concept and the current standards that began in the early 1990s.
These recommendations also reflect consideration of comments received
in response to the committee's initial recommendations as published in
the October 20, 1999 Federal Register (64 FR 56628-56644). The
committee's final recommendations include both modifications and
additions to the initial recommendations.
Decisions on changes to the metropolitan area standards will not
affect the collection, tabulation, and publication of data from Census
2000 and other current Federal data collections for geographic areas
such as states, counties, county subdivisions, and municipalities. In
addition, the Census Bureau will tabulate and publish data from Census
2000 for all metropolitan areas in existence at the time of the census.
DATES: To ensure consideration during the final decision making
process, OMB must receive all written comments no later than October 6,
2000.
ADDRESSES: Please send comments about the committee's final
recommendations to: Katherine K. Wallman, Chief Statistician, Office of
Information and Regulatory Affairs, Office of Management and Budget,
Room 10201 New Executive Office Building, 725 17th Street, NW.,
Washington, DC 20503; fax: (202) 395-7245.
Electronic Availability and Addresses: This Federal Register
Notice, and the two previous Notices related to the review of the
metropolitan area standards, are available electronically from the OMB
web site: http://www.whitehouse.gov/OMB/fedreg/index.html>>. Federal
Register Notices also are available electronically from the U.S.
Government Printing Office web site: http://www.access.gpo.gov/su_docs/
aces/aces140.html>>. Maps portraying the extent of areas that would be
defined if the recommended standards were applied to 1990 census data,
as well as lists of those areas, their components, and principal
cities, are available electronically from the Census Bureau's web site:
http://www.census.gov/population/www/estimates/masrp.html>>. Paper
copies of these additional materials may be obtained by calling (301)
457-2419.
FOR FURTHER INFORMATION CONTACT: James D. Fitzsimmons, Chair,
Metropolitan Area Standards Review Committee, (301) 457-2419; or E-mail
pop.frquestion@census.gov>>.
SUPPLEMENTARY INFORMATION:
Outline of Notice
1. Background
2. Review Process
3. Summary of Comments Received in Response to the October 20, 1999
Federal Register Notice
4. Overview of Final Recommendations From the Metropolitan Area
Standards Review Committee
5. Specific Issues for Comment
Appendix--Final Report and Recommendations From the Metropolitan
Area Standards Review Committee to the Office of Management and
Budget Concerning Changes to the Standards for Defining Metropolitan
Areas
A. Discussion of Final Recommendations
B. Comparison of 1990 Metropolitan Area Standards With the
Recommended 2000 Metropolitan and Micropolitan Area Standards
C. Recommended Standards for Defining Metropolitan and Micropolitan
Areas
D. Key Terms
1. Background
The metropolitan area program has provided standard statistical
area definitions for 50 years. In the 1940s, it became clear that the
value of metropolitan data produced by Federal agencies would be
greatly enhanced if agencies used a single set of geographic
definitions for the Nation's largest centers of population and
activity. OMB's predecessor, the Bureau of the Budget, led the effort
to develop what were then called ``standard metropolitan areas'' in
time for their use in 1950 census reports. Since then, comparable data
products for metropolitan areas have been available.
The general concept of a metropolitan area is that of an area
containing a large population nucleus and adjacent communities that
have a high degree of integration with that nucleus. The purpose of the
metropolitan area standards is to provide nationally consistent
definitions for collecting, tabulating, and publishing Federal
statistics for a set of geographic areas. OMB establishes and maintains
these areas solely for statistical purposes. In reviewing and revising
the areas, OMB does not take into account or attempt to anticipate any
public or private sector nonstatistical uses that may be made of the
definitions. These areas are not designed to serve as a general purpose
geographic framework applicable for nonstatistical activities or for
use in program funding formulas.
OMB discussed the evolution of the standards for defining
metropolitan areas in detail in its December 21, 1998 Federal Register
Notice, ``Alternative Approaches to Defining Metropolitan and
Nonmetropolitan Areas'' (63 FR 70526-70561). Table 1 of that Notice
summarized the evolution of metropolitan area standards since 1950. The
Notice includes the standards that were used to define metropolitan
areas during the 1990s.
OMB published the committee's report on its review and initial
recommendations to OMB as part of the October 20, 1999 Federal Register
Notice entitled, ``Recommendations From the Metropolitan Area Standards
Review Committee to the Office of Management and Budget Concerning
Changes to the Standards for Defining Metropolitan Areas' (64 FR 56628-
56644). In that Notice, the committee recommended the creation of a
``Core Based Statistical Area'' (CBSA) classification. That Notice also
included four maps, as well as a table that compared the 1990
metropolitan area standards with the committee's initial
recommendations for revised standards.
2. Review Process
From the beginning, OMB has reviewed the metropolitan area
standards and, if warranted, revised them in the years preceding their
application to new decennial census data. Periodic review of the
standards is necessary to ensure their continued usefulness and
relevance. The current review of the metropolitan area standards--the
Metropolitan Area Standards Review Project--is the fifth such review.
It addresses, as a first priority, users' concerns with the conceptual
and operational complexity of the standards as they have evolved over
the decades. Other key concerns of the review have been whether and
how:
o To modify the standards further to stay abreast of changes
in population distribution and activity patterns;
[[Page 51061]]
o To use advances in computer applications to consider new
approaches to defining areas; and
o To capture a more complete range of U.S. settlement and
activity patterns than the 1990 standards.
The committee has addressed a number of specific, major issues:
o Whether the Federal Government should define metropolitan
and nonmetropolitan statistical areas;
o What geographic units--``building blocks''--should be used
in defining the statistical areas;
o What criteria should be used to group together such
building blocks in defining the statistical areas;
o Whether the statistical areas should account for all
territory of the Nation;
o Whether there should be hierarchies or multiple sets of
statistical areas in the classification;
o What kinds of entities should receive official recognition
in the classification;
o Whether the classification should reflect statistical
rules only or allow a role for local opinion; and
o How frequently statistical areas should be updated.
The review has included several Census Bureau research projects,
open conferences held in November 1995 and January 1999, a
congressional hearing in July 1997, presentations at professional and
academic conferences, and meetings with Federal, state, and local
officials. The December 1998 and October 1999 Federal Register Notices
discuss these activities in detail.
In the fall of 1998, OMB chartered the Metropolitan Area Standards
Review Committee and charged it with examining the 1990 metropolitan
area standards in light of work completed earlier in the decade and
providing recommendations for possible changes to those standards.
Agencies represented on the committee include the Bureau of the Census
(Chair), Bureau of Economic Analysis, Bureau of Labor Statistics,
Bureau of Transportation Statistics, Economic Research Service
(Agriculture), National Center for Health Statistics, and, ex officio,
OMB. The Census Bureau provides research support to the committee.
This is the third Notice that seeks public comment. The December
1998 Federal Register Notice presented four alternative approaches to
defining metropolitan and nonmetropolitan areas. The October 1999
Federal Register Notice presented the committee's initial
recommendations to OMB. OMB sought and received comments on the issues,
approaches, and recommendations outlined in these Notices. In
developing the final recommendations set forth in this Notice, the
committee has continued its work based on the earlier research and has
considered all of the comments received in response to previous
Notices, as well as comments received at numerous meetings where the
proposals under consideration were discussed.
Ongoing research projects will improve our understanding of the
Nation's patterns of settlement and activity and the ways in which the
patterns can be portrayed. Research will continue into aspects of all
of the alternative approaches presented in the December 1998 Notice.
For example, Census Bureau staff are investigating the feasibility of
developing a census tract level classification to identify settlement
and land use categories along an urban-rural continuum. The Census
Bureau has a project to conduct additional research on the comparative
density approach outlined in the December 1998 Notice. It also is
continuing research on potential uses of directional commuting
statistics and commodity flow data in defining statistical areas. The
Economic Research Service, in conjunction with the Office of Rural
Health Policy in the Department of Health and Human Services and the
University of Washington, has developed a nationwide census tract level
rural-urban commuting area classification. This classification is
available from the Economic Research Service web site: http://
www.ers.usda.gov:80/briefing/rural/ruca/rucc.htm. In addition, the
Census Bureau is investigating the feasibility of defining statistical
areas that would better describe the functional relationships between
geographic areas within the large, densely settled urban areas. These
research efforts may lead to pilot projects of the Census Bureau or
other agencies.
3. Summary of Comments Received in Response to the October 20, 1999
Federal Register Notice
The October 20, 1999 Federal Register Notice requested comment on
the committee's initial recommendations to OMB concerning revisions to
the standards for defining metropolitan areas. OMB received a total of
673 comments, including some that arrived after the December 30, 1999,
deadline.
OMB received 167 comment letters and 34 E-mail messages on a
variety of issues from individuals (72), municipalities (39),
nongovernmental organizations (38), state governmental agencies (18),
regional governmental and planning organizations (14), Federal agencies
(10), and Members of Congress (10). In addition, it received 404
letters and 68 E-mail messages from individuals and organizations
regarding the situation of Schuylkill County, Pennsylvania.
Eight commenters addressed the committee's recommendations about
the qualification requirements for areas and central counties. Three
commenters supported the committee's recommendation that areas should
qualify for CBSA status if a core of sufficient size--a Census Bureau
defined urban cluster of at least 10,000 population or an urbanized
area of at least 50,000 population--was present. (In this Notice, the
term ``urban cluster'' replaces the term ``settlement cluster'' that
was used in the October 1999 Federal Register Notice.) Two commenters
expressed concern that some current metropolitan areas that qualify
based on the presence of a city of at least 50,000 population might not
qualify as a macropolitan area under the recommended standards if an
urbanized area is not present. They suggested including criteria in the
new standards that would either (1) allow an area that contains a city
of 50,000 or more population, but not an urbanized area, to qualify as
a macropolitan area or (2) ``grandfather'' current metropolitan
statistical areas. Three commenters questioned the way in which the
recommended standards would use urban clusters and urbanized areas as
cores to qualify central counties, in particular when a core crosses
county lines, but the portion of the core in one county is not
sufficient to qualify that county as central.
Many comments addressed whether core population or total area
population should be used to determine the level to which each CBSA is
assigned. Two commenters supported using total population of the CBSA
to determine the level; one pointed out that by using core population
to assign levels, it would be possible to have a micropolitan area with
a greater total CBSA population than the total population of a
macropolitan area. Two commenters suggested that the level to which a
CBSA is assigned should be based on the population of the largest core
in the area rather than on the total population in all cores. More than
470 commenters suggested that a county with a total population of at
least 100,000 should qualify as a macropolitan area solely on that
basis, even though its core population is less than 50,000; all but one
of these commenters were specifically
[[Page 51062]]
concerned with Schuylkill County, Pennsylvania.
OMB received 29 comments about terminology and the number of levels
in the proposed CBSA standards. Six commenters argued that the core
population size range recommended for the macropolitan area level was
too broad and suggested that the standards should include five levels
of areas instead of the recommended four. Six commenters favored use of
the terms ``metropolitan'' and ``nonmetropolitan.'' One commenter
favored using ``metropolitan'' and ``nonmetropolitan,'' but also
supported recognizing micropolitan areas as a subset of nonmetropolitan
areas. Two additional commenters supported using the term
``metropolitan,'' but one of them suggested not using the term
``nonmetropolitan.'' Another commenter supported a metropolitan/
nonmetropolitan breakdown, but suggested classifying metropolitan areas
into small, midsize, and large categories with core population
thresholds of 50,000, 250,000, and 1,000,000, respectively. Two
commenters argued that if the CBSA standards were to include several
levels, these levels should be denoted with a numbering or lettering
system instead of using specific terms. Some of these commenters and
others opposed the use of the terms ``megapolitan,'' ``macropolitan,''
and ``micropolitan'' because they found them confusing. Other
commenters suggested ``community statistical area'' to replace ``core
based statistical area,'' and ``nanopolitan'' to replace ``outside core
based statistical area.'' Three commenters suggested that all territory
in the United States should be classified in the new system, and no
area should be classified as a ``non-'' or ``outside'' area.
Forty-two commenters remarked on the committee's recommendation to
use counties as the building block for CBSAs. Seventeen commenters
supported the use of counties, and 25 favored census tracts or some
other subcounty unit. One commenter suggested that if counties are used
as building blocks, subcounty commuting data should be provided to data
users. Nineteen commenters favored the use of minor civil divisions as
building blocks; 18 of these commenters specifically favored the use of
minor civil divisions as the building block for a primary set of areas
in New England.
Eighteen commenters responded about the use of commuting data in
the standards for qualifying outlying counties as well as mergers and
combinations of adjacent CBSAs. Six commenters supported a 25 percent
commuting threshold for outlying county qualification as the committee
recommended; two suggested a 20 percent threshold. One commenter
questioned the rationale behind raising the commuting threshold to 25
percent from the 15 percent threshold that has been in the standards
since they were developed, arguing that raising the threshold to 25
percent will omit many counties that realistically are within the
core's labor market. Two commenters expressed general support for the
committee's recommendations. Seven commenters, however, expressed
concerns that commuting data alone cannot measure all kinds of social
and economic interactions between areas. One of these commenters
suggested using population density data as an additional measure. One
commenter noted that journey-to-work data alone are not sufficient to
determine whether sufficient ties exist to warrant merging or combining
two adjacent CBSAs.
Two commenters supported the committee's recommendations on mergers
and three supported its recommendations on combinations. Two commenters
suggested that local opinion should play a larger role in determining
whether two adjacent areas should merge or combine.
Seventy-one commenters responded about the recommended criteria for
titling CBSAs. Sixty-four of these 71 commenters remarked specifically
on the impact that these criteria would have on the titles of current
metropolitan areas in North Carolina. Seven commenters responded
regarding the potential title of the current Norfolk-Virginia Beach-
Newport News, VA-NC Metropolitan Statistical Area.
Forty-two commenters responded about the lack of recommended
criteria for subdividing the largest CBSAs to form smaller component
groupings of counties. All but one of these commenters favored
development of criteria for subdividing areas. Twenty-six of these
commenters were concerned with New Jersey or Long Island; their remarks
pertained specifically to the perceived need for smaller groupings of
counties within the New York and Philadelphia megapolitan areas to
provide greater detail for data users. One commenter did not favor
subdividing the New York megapolitan area. Sixteen commenters who
favored subdividing CBSAs focused on Massachusetts; their remarks
pertained primarily to the need for subdivisions of the Boston area.
Twenty-three commenters raised questions about the potential impact
of the recommended standards on various nonstatistical programs,
particularly those involving funding. Some commenters suggested that
there should be a study to provide information about the current
nonstatistical programmatic uses of metropolitan areas and the
potential effect of new standards on existing programs.
Five commenters expressed concerns about the comparability of data
provided under the 1990 standards and the proposed standards. They
suggested that statistical areas should be defined for a period after
the 2000 census using both the old and the new standards. Two
commenters remarked on the confusion between the urban/rural and
metropolitan/nonmetropolitan classifications. Both of these commenters
suggested that a single classification that unambiguously identifies
metropolitan, nonmetropolitan, urban, and rural without any overlapping
of these concepts should be developed by OMB. Similarly, one commenter
stated that the classification should include specific criteria for
identifying rural areas.
The committee took all of these comments into account, giving them
careful consideration. As outlined below, it adopted some of these
suggested changes and modified its recommendations to OMB as a result
of the comments. In a number of other cases, however, the committee
concluded that it could not adopt the suggestions made by commenters
without undermining efforts to achieve a consistent, national approach
designed to enhance the value of metropolitan data produced by Federal
agencies.
4. Overview of Final Recommendations From the Metropolitan Area
Standards Review Committee
This Federal Register Notice makes available for comment the
committee's final recommendations to OMB on how the current
metropolitan area standards should be revised. These recommendations
are presented in their entirety in the ``Final Report and
Recommendations From the Metropolitan Area Standards Review Committee
to the Office of Management and Budget Concerning Changes to the
Standards for Defining Metropolitan Areas,'' provided in the appendix
to this Notice. Section C of the appendix presents for public comment
the specific standards recommended by the committee for adoption by
OMB.
The committee recommends a classification based on densely settled
concentrations of population called ``cores.'' The cores for this
classification would be Census Bureau defined
[[Page 51063]]
urbanized areas of 50,000 or more population and smaller urban clusters
of 10,000 to 49,999 population that will be identified using Census
2000 data. Defining a CBSA would require the presence of at least one
core of 10,000 or more population. The recommended CBSA classification
has two categories of areas: (1) Metropolitan areas defined around at
least one urbanized area of 50,000 or more population; and (2)
micropolitan areas defined around at least one urban cluster of 10,000
to 49,999 population. The recommendation to identify micropolitan areas
extends the classification to smaller population centers that in
earlier decades would have been in a ``nonmetropolitan residual.'' The
title for the new classification would be ``Standards for Defining
Metropolitan and Micropolitan Areas.''
These recommendations include a change from the committee's initial
recommendation to identify ``megapolitan areas,'' based on one or more
cores with a total core population of at least one million, and
``macropolitan areas,'' based on one or more cores with a total core
population of 50,000 to 999,999. The committee recommends that
additional research be undertaken to study the analytical utility of
various categories based on population size, and more specifically, to
determine meaningful size thresholds for such categories. In addition,
these recommendations include a change from the committee's initial
recommendation to base categories of areas on the total population in
all cores within a CBSA.
The committee recommends the use of counties and equivalent
entities as the building block for CBSAs throughout the United States,
Puerto Rico, and Island Areas, including the use of counties as
building blocks for CBSAs in New England. The committee also recommends
that minor civil divisions be used as building blocks for a set of
statistical areas conceptually similar to CBSAs for the New England
states only.
The committee recommends identifying principal cities within CBSAs.
It also recommends that component entities comprising one or more
counties be identified within CBSAs that contain a single core with 2.5
million or more population. These component entities would be termed
``metropolitan divisions.'' (The committee's recommendations would
extend this practice to the minor civil division based areas in New
England.) This recommendation is an addition to the initial
recommendations. The committee recommends titling each metropolitan
division using the names of up to three principal cities within the
metropolitan division, in order of descending city population size. If
there are no principal cities located within a metropolitan division,
the committee recommends including in the title the names of up to
three counties in order of descending population size.
The committee recommends combining adjacent CBSAs when their
employment interchange rate is at least 15. The areas that combine also
would retain their identities as separate metropolitan and micropolitan
areas.
5. Specific Issues for Comment
With this Notice, OMB requests comment on all of the final
recommendations of the Metropolitan Area Standards Review Committee
concerning revisions to the current standards for defining metropolitan
areas. The standards recommended to OMB for adoption appear in Section
C of the appendix to this Notice. Section A of the appendix provides a
discussion of the recommendations on the various issues considered by
the committee. Section B of the appendix presents a comparison of the
1990 metropolitan area standards with the recommended Metropolitan and
Micropolitan Area Standards.
OMB notes that there were several issues on which comment was
received, but on which the committee has not changed its initial
recommendations, including the use of population in cores (in contrast
to total area population) as a means of determining a CBSA's category
(metropolitan or micropolitan), and the use only of the name of the
largest principal city in each of up to three CBSAs that combine to
title Combined Areas.
OMB particularly seeks comment on those final recommendations that
differ from the committee's initial recommendations published in the
October 20, 1999 Federal Register. These are the recommendations about
the:
o Number of categories of CBSAs and the terms by which they
would be identified (see Section A.1);
o Categorization of CBSAs on the basis of population in
cores (Section A.1);
o Identification of New England City and Town Areas (NECTAs)
to indicate that NECTAs are conceptually similar to CBSAs (Section
A.2);
o Criteria for qualifying a central county (Section A.3);
o Identification of metropolitan divisions within CBSAs with
a core of 2.5 Million or more population and NECTA divisions within
NECTAs that have a core of that size (Section A.7); and
o Criteria for titling Combined Areas, which would now
require that the second- and third-largest CBSAs in a Combined Area
each have at least one-third the population of the largest area for
their single largest principal cities to appear in the title (Section
A.9).
OMB would appreciate receiving views and comments on any aspects of
the recommended standards.
John T. Spotila,
Administrator, Office of Information and Regulatory Affairs.
Appendix--Final Report and Recommendations From the Metropolitan Area
Standards Review Committee to the Office of Management and Budget
Concerning Changes to the Standards for Defining Metropolitan Areas
Transmittal Memorandum
July 6, 2000.
Memorandum for Katherine K. Wallman, Chief Statistician, Office of
Management and Budget
From: Metropolitan Area Standards Review Committee
Subject: Transmittal of Final Report and Recommendations Concerning
Changes to the Standards for Defining Metropolitan Areas
We are pleased to transmit to you the attached report presenting
this committee's final recommendations for modifying the Office of
Management and Budget's (OMB's) standards for defining metropolitan
areas. They represent our best technical and professional advice for
how the standards could better account for and describe changes in
settlement and activity patterns throughout the United States, Puerto
Rico, and the Island Areas, yet still meet the data reporting needs and
requirements of Federal agencies and the public. In developing these
final recommendations, we have continued our review of work completed
over the past several years, and we have considered and discussed
comments that were received in response to our initial recommendations
published in the October 20, 1999 Federal Register. In addition to a
discussion of our final recommendations, we are providing a comparison
of the standards we propose with the 1990 metropolitan area standards.
We also are providing the specific standards recommended by the
committee and definitions of key terms used in this report.
[[Page 51064]]
We hope that OMB will find these final recommendations informative
and helpful in making its decision on what changes, if any, to adopt in
the standards for defining geographic areas for collecting, tabulating,
and publishing Federal statistics.
Attachment--Final Report and Recommendations from the Metropolitan
Area Standards Review Committee to the Office of Management and
Budget Concerning Changes to the Standards for Defining
Metropolitan Areas
A. Discussion of Final Recommendations
1. Recommendations Concerning Categories and Terminology for a Core
Based Statistical Area (CBSA) Classification to Be Titled ``Standards
for Defining Metropolitan and Micropolitan Areas''
The Metropolitan Area Standards Review Committee recommends
adoption of a CBSA classification that uses densely settled
concentrations of population (cores) for the qualification of areas.
The classification would be titled ``Standards for Defining
Metropolitan and Micropolitan Areas.'' The committee recommends a
minimum population size of 10,000 for a core that would qualify a CBSA.
Those CBSAs that are associated with at least one core of 50,000 or
more population (an urbanized area) should be categorized as
metropolitan areas. Those CBSAs that are associated with at least one
core of 10,000 to 49,999 population (an urban cluster), but no single
core of 50,000 or more population, should be categorized as
micropolitan areas. Under these recommended standards, nearly 90
percent of the U.S. population would reside in micropolitan and
metropolitan areas.
Territory not included in CBSAs should be referred to as being
``outside core based statistical areas.'' The committee suggests that
additional research be done to identify methods for defining and
categorizing territory outside CBSAs to attain an area classification
that applies to the entire Nation.
The committee considered the following sometimes incompatible
concerns as it developed size categories and terminology:
o Eliminating the current metropolitan/nonmetropolitan
dichotomy and replacing it with a range of categories that more
meaningfully represent the settlement and activity patterns of the
Nation;
o Introducing specific terms for areas containing cores of
1,000,000 or more persons and cores of 250,000 to 999,999 persons,
respectively;
o Evaluating advantages and disadvantages of retaining the
1990 metropolitan area standards' core population threshold of 50,000;
o Assessing advantages and disadvantages of retaining the
metropolitan/nonmetropolitan terminology of the 1990 standards; and
o Maintaining simplicity.
Broad agreement existed in favor of establishing a micropolitan
area category as a means of distinguishing between (1) areas integrated
with smaller centers of population and activity and (2) territory not
integrated with any particular population center. Defining micropolitan
areas represents a response to comments that a revised classification
should cover a broader range of population and economic activity
patterns than the 1990 standards. The committee also considered various
combinations of population distribution and economic activity pattern
measures to classify counties not included in a CBSA, but none offered
a satisfactory method of meaningfully accounting for these counties in
the recommended classification.
The categories and terminology recommended here constitute a change
from the committee's initial recommendations as reported in the October
20, 1999 Federal Register Notice. The changes in terminology are a
response to public comment that urged retention of the term
``metropolitan'' in the revised standards because of its familiarity
and broad usage among data users and the general public.
The committee considered two issues when discussing the basis for
categorizing CBSAs as either metropolitan or micropolitan. The first of
these issues was whether to base categorization on the total CBSA
population or on core population. The committee agreed that since cores
are the organizing entities of CBSAs, categorization should be on the
basis of the population in cores, reasoning that the range of services
and functions provided within an area largely derive from the size of
the core.
The second issue was whether to categorize areas based on the
population of the most populous (or ``dominant'') core or on the total
population of all (or ``multiple'') cores within a CBSA. The
committee's initial recommendation suggested categorizing areas on the
basis of the total population in all cores within a CBSA. In reaching
this decision, the committee reasoned that because all cores play a
role in determining the extent of a CBSA, all should be taken into
account when categorizing that CBSA. Although commuting is measured
from county to county, most workers commute to specific cores. When
there are multiple cores within a CBSA, each core plays a role in the
qualification of outlying counties. Some committee members argued,
however, that a single core of 50,000 or more population provides a
wider variety of functions and services than does a group of smaller
cores, even when such a group may have a collective population greater
than 50,000. These committee members were concerned that CBSAs
categorized as metropolitan on the basis of the population in all cores
would not bear the same kinds of characteristics as CBSAs categorized
as metropolitan areas on the basis of a single core of 50,000 or more
population.
In reaching the decision to categorize CBSAs on the basis of the
population in the largest core, the committee agreed that this is a
complex issue that, in part, is reflected in the ongoing debate
regarding the current nature of urbanization and urban systems. In the
past, metropolitan areas tended to be dominated by a single core,
consisting largely of a populous city and its adjacent densely settled
suburbs. The dispersal of residential locations and economic activities
that has occurred in some areas over the past 50 years, however, has
resulted in multiple cores, each of which may provide specialized
functions that contribute to the social and economic well-being of the
entire area. The extent of the spheres of influence of the various
cores may vary and overlap depending on the kinds of functions or
services provided. One core may play a greater, or more dominant, role
in organizing and influencing the social and economic activity of a
particular CBSA. At the same time, its influence could be supplemented
or possibly matched by additional cores within the same CBSA. The
committee recommends further research on the functional integration of
multiple, noncontiguous cores.
While recognizing the usefulness of standard size categories for
CBSAs for tabulating data, the committee was less certain regarding the
significance of specific population thresholds as a means of
identifying functional differences between different sizes of areas.
The committee therefore does not recommend delineations of categories
of CBSAs with core populations greater than 50,000 and has dropped the
``megapolitan'' and ``macropolitan'' area categories set forth in its
initial recommendations. The committee
[[Page 51065]]
recommends retaining the population threshold of 50,000 to distinguish
between micropolitan and metropolitan areas, primarily to maintain
comparability with previous definitions of metropolitan areas. The
committee concluded that additional research is needed to identify
optimal population thresholds for categories of CBSAs. In the meantime,
users can group the areas that would be defined as ``metropolitan'' by
size to meet their particular research needs.
2. Recommendations Concerning the Geographic Unit to Be Used as the
Building Block for Defining CBSAs
Counties and equivalent entities should be used as building blocks
for CBSAs throughout the United States, Puerto Rico, and the Island
Areas. Minor civil divisions should be used as the building block for a
set of areas, similar in concept to CBSAs, in New England only. Using
counties and equivalent entities throughout the United States and
Puerto Rico continues current practice, except in New England, where
historically metropolitan areas have been defined using minor civil
divisions.
The choice of a geographic unit to serve as the building block can
affect the geographic extent of a statistical area and its relevance or
usefulness in describing economic and demographic patterns. The choice
also has implications for the ability of Federal agencies to provide
data for statistical areas and their components. The December 1998
Federal Register Notice, ``Alternative Approaches to Defining
Metropolitan and Nonmetropolitan Areas,'' presented advantages and
disadvantages of five potential building blocks. Each of these units
was evaluated in terms of its consistency in delineation across the
Nation, data availability, boundary stability, and familiarity.
The advantages of using counties and their equivalents are that
they are available for the entire country, have stable boundaries, and
represent familiar geographic entities. In addition, more Federal
statistical programs produce data at the county level than at any
subcounty level. The committee decided that the well-known
disadvantages of counties as the building block for statistical areas--
the large geographic size of some counties and the lack of geographic
precision that follows from their use--were outweighed by the
advantages offered by counties.
In reaching its recommendation to use counties as the building
block for CBSAs in New England, the committee attached priority to the
use of a consistent geographic unit nationwide. Use of a consistent
geographic building block offers improved usability to producers and
users of data; data for CBSAs in all parts of the country would be
directly comparable. In addition, some statistical programs, such as
those providing nationwide economic data and population estimates,
regard the metropolitan area program's use of minor civil divisions in
New England as a hindrance. They have sometimes used the currently
available alternative county based areas for New England, known as the
New England County Metropolitan Areas (NECMAs), or have minimized the
number of data releases for metropolitan areas. Under the current
metropolitan area program, then, data producers and users typically
choose between (1) adhering to the preferred Metropolitan Statistical
Areas, Consolidated Metropolitan Statistical Areas, and Primary
Metropolitan Statistical Areas throughout the country and having data
that limit comparisons between some areas, and (2) using alternative
areas in New England and having more comparable data. The committee's
recommendation eliminates the need for this choice.
Demographic and economic data for minor civil divisions in New
England are more plentiful, however, than are such data for subcounty
entities in the rest of the Nation. In recognition of the importance of
minor civil divisions in New England, the wide availability of data for
them, and their long-term use in the metropolitan area program, the
committee recommends also using minor civil divisions as building
blocks for a set of areas for the six New England states. These New
England City and Town Areas (NECTAs) would be intended for use in the
collection, tabulation, publication, and analysis of statistical data,
whenever feasible and appropriate, for New England. Data providers and
users desiring areas defined using a nationally consistent geographic
building block should consider using the county based CBSAs in New
England; however, counties are less well-known in New England than
cities and towns.
3. Recommendations Concerning Cores of CBSAs and Central Counties
Census Bureau defined urbanized areas of 50,000 or more population
and Census Bureau defined urban clusters of at least 10,000 population
should be used as the cores of CBSAs. Identification of ``central
counties'' should be based on the locations of the cores.
The recommended use of urbanized areas as cores is consistent with
current practice. To extend the classification to areas based on cores
of 10,000 to 49,999 population, the committee recommends the use of
urban clusters, which the Census Bureau will identify following Census
2000. This change would permit a fuller accounting of the distribution
of population and economic activity across the territory of the Nation
than is provided by the current metropolitan area standards. Following
from this recommendation, an urban area of at least 10,000 population
would be required for qualifying a CBSA.
The locations of urbanized areas and urban clusters (referred to
collectively as ``urban areas'') should provide the basis for
identifying central counties of CBSAs, which are the counties to and
from which ties are measured in determining the extent of areas. The
committee recommends identifying central counties as those counties
that:
(a) Have at least 50 percent of their population in urban areas
(urbanized area or urban cluster) of at least 10,000 population; or
(b) Have within their boundaries a population of at least 5,000
located in a single urban area (urbanized area or urban cluster) of at
least 10,000 population.
The committee has revised its recommendation concerning criteria
for identifying central counties since its initial recommendations were
published in the October 20, 1999, Federal Register Notice. If a single
urban area of at least 10,000 population has at least 5,000 population
in a county, the committee recommends that the county qualify as a
central county. This recommendation recognizes that a county may
contain a portion of an urbanized area or urban cluster of sufficient
size to act as an employment center for surrounding populations, but of
insufficient size to have accounted for at least 50 percent of the
population of a single urbanized area or urban cluster as required
under the committee's initial recommendation. The choice of 5,000 as
the threshold for central county qualification is consistent with the
initial recommendation's minimum requirement for qualification as a
central county of the smallest permissible core (i.e., 5,000 is 50
percent of the 10,000 population minimum core size).
4. Recommendations Concerning Criteria for Inclusion of Outlying
Counties
Commuting data should be used as the basis for grouping counties
together to form CBSAs (i.e., to qualify ``outlying
[[Page 51066]]
counties''). Measures of settlement structure, such as population
density, should not be used to qualify outlying counties for inclusion
in CBSAs. Three priorities guided the committee in reaching these
recommendations. The data used to measure connections among counties
should (1) describe those connections in a straightforward and
intuitive manner, (2) be collected using consistent procedures
nationwide, and (3) be readily available to the public. These
priorities pointed to the use of data gathered by Federal agencies and,
more particularly, to commuting data from the Census Bureau. Commuting
to work is an easily understood measure that reflects the social and
economic integration of geographic areas.
The recommendation not to use measures of settlement structure
represents a change from the 1990 standards. In those standards,
varying levels of population density, percentage of total population
that is urban, presence of an urbanized area population, and population
growth rate are used in combination with varying levels of commuting to
determine qualification of outlying counties for inclusion in a
metropolitan area. Settlement and commuting patterns, however, have
changed over time as a result of improvements to public transportation;
more and better-maintained roads; and increasing flexibility of some
employers who permit irregular work weeks, flextime, and opportunities
to work at home. The Internet, satellite hookups, and other technology
also have played a role. The committee concluded that, as changes in
settlement, commuting patterns, and communications technologies have
occurred, settlement structure no longer is as reliable an indicator of
metropolitan character as was previously the case.
An outlying county should qualify on the basis of the percentage of
employed residents of the county who work in the CBSA's central county
or counties, or on the basis of the percentage of employment in the
potential outlying county accounted for by workers who reside in the
CBSA's central county or counties. A 25 percent minimum threshold for
each of these measures should be used.
The committee observed that the percentage of a county's employed
residents who commute to the central county or counties is an
unambiguous, clear measure of whether a potential outlying county
should qualify for inclusion. The percentage of employment in the
potential outlying county accounted for by workers who reside in the
central county or counties is similarly a straightforward measure of
ties. Including both criteria addresses the conventional and the less
common reverse commuting flows.
The committee also noted changes in daily mobility patterns and
increased interaction between communities as indicated by increases in
inter-county commuting over the past 40 years. The percentage of
workers in the United States who commute to places of work outside
their counties of residence has increased from a national average of
approximately 15 percent in 1960 (when nationwide commuting data first
became available from the decennial census) to a national average of
nearly 25 percent in 1990. The committee concluded that raising the
commuting percentage required for qualification of outlying counties
from the 15 percent minimum of the 1990 standards to 25 percent was
appropriate against this background of increased overall inter-county
commuting coupled with the removal of all settlement structure measures
from the outlying county criteria. The 25 percent threshold also stood
out as a noticeable divide when reviewing 1990 census data on the
percentage of workers who commute outside their counties of residence.
Counties should qualify for inclusion in a CBSA as outlying
counties on the basis of commuting ties with the central county (or
counties) of that one area only. The committee concluded that outlying
counties should not qualify based on total commuting to central
counties of multiple CBSAs, because that would result in inconsistent
grounds for qualification in an individual area. Throughout its
history, the purpose of the metropolitan area program has been to
identify individual statistical areas, each containing a core plus any
surrounding territory integrated with that core as measured by
commuting ties. The committee saw no reason to depart from that
approach in defining CBSAs.
5. Recommendation Concerning Merging Adjacent CBSAs
Adjacent CBSAs should be merged to form a single CBSA when the
central county or counties of one area qualify as outlying to the
central county or counties of another. The committee determined that
when the central county or counties (as a group) of one CBSA qualify as
outlying to the central county or counties (as a group) of another
area, the two CBSAs should be merged. Because a merger recognizes ties
similar to the ties between an outlying county and the central counties
of a CBSA, the committee recommends that the minimum commuting
threshold similarly be set at 25 percent, measured with respect to all
central counties of one CBSA relative to all central counties of the
other.
6. Recommendations Concerning Identification of Principal Cities
Principal cities in CBSAs should be identified and used to title
the areas. Because the procedures recommended by the committee use
urbanized areas and urban clusters as the organizing entities for
CBSAs, the identification of central cities as required by the 1990
standards for qualifying and defining areas is no longer necessary for
that purpose. Also, while still important, central cities have become
less dominant in the local context over time. Nevertheless, the
committee recognizes that specific cities within individual CBSAs are
important for analytical purposes as centers of employment, trade,
entertainment, and other social and economic activities. The committee
therefore recommends criteria for identifying principal cities and
using the principal cities for titling areas.
The committee recommends that the principal city (or cities) of a
CBSA include:
(a) The largest incorporated place or census designated place in
the CBSA;
(b) Any additional incorporated place or census designated place
with a population of at least 250,000 or in which 100,000 or more
persons work; and
(c) Any additional incorporated place or census designated place
with a population that is at least 10,000 and one-third the size of the
largest place, and in which employment meets or exceeds the number of
employed residents.
The committee recommends using the term ``principal city'' rather
than ``central city.'' The term ``central city'' has come to connote
``inner city'' and thus sometimes causes confusion.
7. Recommendation Concerning Identification of Components within
Metropolitan Areas and NECTAs that Contain at Least One Core of 2.5
Million or More Population
Within metropolitan areas that have at least one core with 2.5
million or more population, metropolitan divisions, consisting of one
or more counties, should be identified. Urbanized areas with very large
populations can extend across multiple counties and even across state
boundaries, and can contain several distinct employment and settlement
centers. Although these centers are part of a single agglomeration of
population and
[[Page 51067]]
activity, the degrees of functional integration between them can vary.
The provision of data for only the entire metropolitan area based on
such large urbanized areas may mask demographic and economic variations
that are important for data users and analysts. To represent the social
and economic variations found within the largest metropolitan areas,
the committee recommends adopting criteria that would identify
components called ``metropolitan divisions,'' which would comprise
counties or groups of counties that function as distinct areas within
the metropolitan area. (Designation of metropolitan divisions would
have no effect on the previously defined central counties of the
metropolitan area; these counties would remain central to the
metropolitan area, regardless of any additional designation they might
be given within metropolitan divisions.)
The committee recommends identifying a county as a ``main county''
of a metropolitan division if:
(a) More than 50 percent of its employed residents work within the
county;
(b) The ratio of the number of jobs located in the county to the
number of employed residents of the county is at least .75; and
(c) The highest rate of out-commuting from the county to any other
county is less than 15 percent.
After all main counties have been identified, each additional
county that already has qualified for inclusion in the metropolitan
area should be included in the metropolitan division associated with
the main county to which the county at issue sends the highest
percentage of its out-commuters. Counties within a metropolitan
division should be contiguous.
Differences in geographic scale between minor civil divisions and
counties necessitate the use of a different set of criteria when
identifying meaningful divisions within NECTAs that contain at least
one core of 2.5 million or more population.
The committee recommends the following criteria for NECTA
divisions:
(a) A city or town is identified as a ``main city or town'' of a
NECTA division if the city or town at issue has a population of 50,000
or more and its highest rate of out-commuting to any other city or town
is less than 20 percent.
(b) After all main cities and towns have been identified, each
additional city and town that already has qualified for inclusion in
the NECTA should be included in the NECTA division associated with the
city or town to which the one at issue sends the highest percentage of
its out-commuters.
The committee also recommends that each NECTA division should
contain a total population of 100,000 or more. Cities and towns at
first assigned to areas with less than 100,000 population subsequently
should be assigned to the qualifying NECTA division associated with the
city or town to which the one at issue sends the highest percentage of
its out-commuters. Cities and towns within a NECTA division should be
contiguous.
In recommending these criteria, the committee recognizes that
cities and towns of 50,000 or more population represent significant
centers around which to organize NECTA divisions; the 50,000 population
threshold is consistent with population thresholds used in current and
past classifications to identify population centers around which
metropolitan area level entities are defined.
These recommendations for identifying metropolitan divisions and
NECTA divisions are additions to the committee's initial
recommendations.
8. Recommendations Concerning Combining Adjacent CBSAs
CBSAs should be combined when entire adjacent areas are linked
through commuting ties. The committee recommends that ties between
adjacent CBSAs that are less intense than those captured by mergers
(see Section A.5), but still significant, be recognized by combining
those CBSAs. Because a combination thus defined represents a
relationship of moderate strength between two CBSAs, the areas that
combine should retain separate identities within the combined area.
Potential combinations should be evaluated by measuring commuting
between entire adjacent CBSAs--commuting of all counties, as a group,
within one CBSA relative to all counties, as a group, in the adjacent
area.
The committee recommends basing combinations on the employment
interchange rate between two CBSAs, defined as the sum of the
percentage of commuting from the CBSA with the smaller total population
to the CBSA with the larger total population and the percentage of
employment in the CBSA with the smaller total population accounted for
by workers residing in the CBSA with the larger total population. The
committee recommends a minimum threshold of 15 for the employment
interchange rate but recognizes that this threshold may result in
combinations where the measured ties are perceived as minimal by
residents of the two areas. The committee therefore recommends
combinations of CBSAs, based on an employment interchange rate of at
least 15 but less than 25, only if local opinion (as discussed in
recommendation 10) in both areas favors the combination. If the
employment interchange rate equals or exceeds 25, combinations should
occur automatically.
9. Recommendations Concerning Titles of CBSAs, Metropolitan Divisions,
NECTA Divisions, and Combined Areas
Each CBSA should be titled using the name of its principal city
with the largest population, as well as the names of the second-and
third-largest principal cities, if multiple principal cities are
present.
Each metropolitan division should be titled using the name of the
principal city with the largest population, as well as the names of the
second- and third-largest principal cities, if multiple principal
cities are present. If there are no principal cities located in the
metropolitan division, the title of the metropolitan division should
include the names of up to three counties in order of descending
population size.
Each NECTA division should be titled using the name of the
principal city with the largest population, as well as the names of the
second- and third-largest principal cities, if multiple principal
cities are present. If there are no principal cities located in the
NECTA division, the title of the NECTA division should include the name
of the city or town with the largest population.
Combined areas should be titled using the name of the largest
principal city in the CBSA with the largest total population that
combines, followed by the name of the largest principal city in each of
up to two additional CBSAs that combine, provided that the second and
third CBSAs in the combined area each have at least one-third of the
total population of the largest CBSA.
Titles provide a means of uniquely identifying individual CBSAs,
metropolitan divisions, NECTA divisions, and combined areas so that
each is recognizable to a variety of data users. As such, the title of
a CBSA, metropolitan division, NECTA division, or combined area should
contain the names of geographic entities located in the area that are
prominent and provide data users with a means of easily identifying the
general location of the CBSA, metropolitan division, or NECTA division
or extent of the combined area.
Finally, any state in which the CBSA, metropolitan division, NECTA
division, or combined area is located also should be included in the
title.
[[Page 51068]]
10. Recommendation Concerning Use of Statistical Rules and the Role of
Local Opinion
Limited use should be made of local opinion in the definition
process. Applying only statistical rules when defining areas minimizes
ambiguity and maximizes the replicability and integrity of the process.
The committee recommends consideration of local opinion only in cases
of CBSA combinations where adjacent CBSAs have an employ