2010 Standards for Delineating Metropolitan and Micropolitan Statistical Areas

AGENCY:

Office of Information and Regulatory Affairs, Office of Management and Budget (OMB), Executive Office of the President.

ACTION:

Notice of decision.

SUMMARY:

This Notice announces OMB's adoption of 2010 Standards for Delineating Metropolitan and Micropolitan Statistical Areas. The 2010 standards replace and supersede the 2000 Standards for Defining Metropolitan and Micropolitan Statistical Areas. In arriving at its decision, OMB accepted the recommendations of the interagency Metropolitan and Micropolitan Statistical Area Standards Review Committee (the Review Committee) as published in the February 12, 2009 Federal Register.

The SUPPLEMENTARY INFORMATION in this Notice provides background information on the standards (Section A), a brief synopsis of the public comments OMB received in response to the February 12, 2009 Federal Register notice (Section B), and OMB's decisions on the recommendations of the Review Committee (Section C). The 2010 standards appear at the end of this Notice (Section D).

The adoption of the 2010 standards will not affect the availability of Federal data for geographic areas such as States, counties, county subdivisions, and municipalities. For the near term, the U.S. Census Bureau will tabulate and publish data from the 2010 Census for all metropolitan, micropolitan, and combined statistical areas in existence at the time of the census.

DATES:

Effective Date: This Notice is effective immediately. OMB plans to announce delineations of areas based on the 2010 standards and 2010 Census data in 2013. Federal agencies should begin to use the new area delineations to tabulate and publish statistics when the delineations are announced.

ADDRESSES:

Please send correspondence about OMB's decision to Katherine K. Wallman, Chief Statistician, Office of Management and Budget, Room 10201, New Executive Office Building, Washington, DC 20503, telephone number (202) 395-3093, fax number (202) 395-7245, or E-mail 2010MetroAreas@omb.eop.gov with the subject 2010 MetroAreas.

Electronic Availability: This notice is available on the Internet from the OMB Web site at http://www.whitehouse.gov/omb/fedreg_default/.

FOR FURTHER INFORMATION CONTACT:

Suzann Evinger, Office of Management and Budget, telephone number (202) 395-3093, fax number 202-395-7245.

SUPPLEMENTARY INFORMATION:

Outline of Notice

A. Background and Review Process

B. Summary of Comments Received in Response to the February 12, 2009 Federal Register Notice

C. OMB's Decisions Regarding Recommendations From the Metropolitan and Micropolitan Statistical Area Standards Review Committee Concerning Changes to the Standards for Defining Metropolitan and Micropolitan Statistical Areas

D. 2010 Standards for Delineating Metropolitan and Micropolitan Statistical Areas and Key Terms

A. Background and Review Process

1. Background

The metropolitan and micropolitan statistical area program, under various names, has provided standard statistical area delineations for approximately 60 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 delineations 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 publications. Since then, comparable data products for metropolitan areas have been available.

The general concept of a metropolitan statistical 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 concept of a micropolitan statistical area closely parallels that of the metropolitan statistical area, but a micropolitan statistical area features a smaller nucleus. The purpose of these statistical areas is unchanged from when metropolitan areas were first delineated: The classification provides a nationally consistent set of delineations for collecting, tabulating, and publishing Federal statistics for geographic areas.

OMB establishes and maintains these areas solely for statistical purposes. In reviewing and revising these areas, OMB does not take into account or attempt to anticipate any public or private sector nonstatistical uses that may be made of the delineations. These areas are not designed to serve as a general-purpose geographic framework applicable for nonstatistical activities or for use in program funding formulas.

Furthermore, the Metropolitan and Micropolitan Statistical Area Standards do not produce an urban-rural classification, and confusion of these concepts can lead to difficulties in program implementation. Counties included in Metropolitan and Micropolitan Statistical Areas and many other counties may contain both urban and rural territory and population. For instance, programs that seek to strengthen rural economies by focusing solely on counties located outside metropolitan statistical areas could ignore a predominantly rural county that is included in a metropolitan statistical area because a high percentage of the county's residents commute to urban centers for work. OMB urges agencies, organizations, and policy makers to review carefully the goals of nonstatistical programs and policies to ensure that appropriate geographic entities are used to determine eligibility for the allocation of Federal funds.

2. Review Process

From the beginning of the program, OMB (or its predecessor) has reviewed the metropolitan (and now micropolitan) statistical area standards and, if warranted, revised them in the years preceding their application to new decennial census data. During the 1990s, OMB conducted a comprehensive review of the 1990 standards, leading to the development of the core based statistical areas (CBSAs) (metropolitan and micropolitan statistical areas) and combined statistical areas as contained in the 2000 standards (available at: http://www.whitehouse.gov/omb/fedreg/metroareas122700.pdf ). Periodic review of the standards is necessary to ensure their continued usefulness and relevance. The current review of the metropolitan and micropolitan statistical area standards is the sixth such review.

In 2008, OMB charged the Metropolitan and Micropolitan Statistical Area Standards Review Committee with examining the 2000 metropolitan and micropolitan statistical area standards and providing to OMB recommendations for revising the standards that would be issued no later than December 2010. Agencies represented on the Review Committee included the Census Bureau (Chair), Bureau of Economic Analysis, Bureau of Labor Statistics, Bureau of Transportation Statistics, Economic Research Service/U.S. Department of Agriculture, National Center for Health Statistics, and ex officio, OMB. The Census Bureau provided research support to the committee.

During the five years between the 2000 standards' implementation in 2003 and the commencement of the Review Committee's deliberations in 2008, OMB received very few inquiries from the public questioning the conceptual framework of the 2000 standards and the resulting area delineations. Therefore, the Review Committee concluded early in its deliberations that the 2000 standards worked well and were generally accepted. Thus, the Review Committee determined that it would not be necessary or appropriate to seek wide-ranging public comment on all aspects of the 2000 standards, particularly since a multiyear conceptual review, with several rounds of public comment, had been conducted prior to their adoption. Instead, the Review Committee decided to limit its review, and subsequent recommendations, to a small set of issues associated with the implementation of the 2000 standards.

OMB published the Review Committee's recommendations for revisions to the 2000 standards in a February 12, 2009 Federal Register notice entitled “Recommendations From the Metropolitan and Micropolitan Statistical Area Standards Review Committee to the Office of Management and Budget Concerning Changes to the 2000 Standards for Defining Metropolitan and Micropolitan Statistical Areas” (74 FR 7172-7177).

B. Summary of Comments Received in Response to the February 12, 2009 Federal Register Notice

The February 12, 2009 Federal Register notice requested comment on the Review Committee's recommendations to OMB concerning revisions to the 2000 Standards for Defining Metropolitan and Micropolitan Statistical Areas, namely its recommendations concerning (1) the qualification and titling of combined statistical areas; (2) the updating of metropolitan and micropolitan statistical areas; and (3) the replacement of the word “definition” with the word “delineation.” To help ensure the clarity of the 2010 recommended standards, OMB also requested comments on the wording of the standards.

OMB received 40 comment letters in response to the February 12, 2009 notice.

Five commenters remarked on aspects of the Review Committee's recommendations for eliminating local opinion from the qualification of combined statistical areas and establishing a minimum employment interchange measure of 15 for the automatic qualification of combined statistical areas. Two commenters supported the elimination of local opinion in combined statistical area qualification, with one of the two expressing concern about setting the minimum employment interchange measure threshold at 15. Two other commenters expressed concern about both the potential consequences of eliminating local opinion and setting the automatic threshold at 15. One commenter supported setting the employment interchange measure at 15 for combining areas.

Two commenters remarked on the proposed combined statistical area titling criteria. One commenter supported the committee's recommendation, while the other commenter wondered if eliminating local opinion would end potentially positive means of allowing individual areas to express their opinions.

Five commenters remarked on aspects of the Review Committee's recommendations concerning the update of metropolitan and micropolitan statistical areas, including (1) the limiting of yearly updates as well as (2) the planned update in 2018. All five commenters who offered views on limiting yearly updates agreed with the Review Committee, as did all four who offered views on the planned update in 2018.

Three commenters remarked on the Review Committee's recommendation to replace the term “definition” with “delineation”: Two agreed, while one was indifferent. One of the three commenters wondered if it would take a long period for the new term to gain general acceptance.

OMB has reviewed these comments, giving them careful consideration. In some cases, however, we have concluded that we could not adopt the suggestions made by commenters, particularly with respect to the qualification and titling of combined statistical areas, without undermining efforts to achieve a consistent, national approach designed to enhance the value of data produced by Federal agencies.

In addition to the recommendations on which OMB requested comment, individuals also offered comments—not requested by OMB—on other aspects of the standards and the program. As indicated in the February 12, 2009, Federal Register notice, the 2000 standards were the result of an extensive and comprehensive review. In conducting the recent review, the Review Committee concluded that the 2000 standards have worked well during the past decade, and recommended only some modest specific changes on which OMB sought public comments. The comments summarized below relate to aspects of the statistical area standards that were not open for public comment.

One commenter suggested alternative means of titling metropolitan statistical areas with more than one county: (1) Titling based on the county seat of each county in the metropolitan statistical area; or (2) listing the most populous urban centers of each county. Another commenter suggested that titling a merged metropolitan statistical area be based on the names of the areas being merged. Two commenters asked OMB to consider shorter titles for areas.

One commenter suggested that the central county criteria be modified so that section 2(b) is used in a much more limited fashion, only applying that criterion to those potential metropolitan and micropolitan statistical areas that would otherwise not contain a central county.

One commenter suggested an alternative method of qualifying outlying counties that measures commuting to the central counties and does not require adjacency to the balance of the area. One commenter questioned the sole reliance on commuting for outlying county criteria, while two other commenters suggested that the outlying county criteria should be modified to follow the outlying county criteria in the 1990 OMB standards, rather than the 2000 OMB standards. One commenter suggested the use of the employment interchange measure, as well as a measure of “outleakage” of consumer spending, to qualify counties to a county that contains a principal city.

Thirteen commenters expressed concern about the current delineations of the Greensboro-High Point, Winston-Salem, and Burlington, North Carolina metropolitan statistical areas, and suggested that OMB find ways to merge or otherwise bring together the three individual areas—and in the case of a few commenters, additional territory—into a single metropolitan statistical area.

Four commenters expressed concerns about the current delineations of selected CBSAs in Michigan. All four commenters suggested a reconfiguration of the Grand Rapids area, with two of the four also questioning the delineation of selected other areas in the State.

One commenter suggested that the term “metropolitan statistical area” only apply to those areas that do not belong to combined statistical areas. This commenter further suggested that components of combined statistical areas should be designated using some other category name.

One commenter suggested that OMB consider separate coding sequences for metropolitan statistical areas and for micropolitan statistical areas, and that OMB consider using headings such as “Metropolitan CBSAs” and “Micropolitan CBSAs.” Also, one commenter asked OMB to consider maintaining the same statistical area codes for areas delineated in the update scheduled for 2018 as will have been established in the review scheduled for 2013, including cases where titles have changed but where boundaries have not changed. Furthermore, the commenter also suggested that OMB consider an interagency process to investigate the feasibility of creating classifications of territory within metropolitan statistical areas.

Some out-of-scope comments focused on the use of the statistical areas, including the presentation of data. One commenter asked OMB to consider researching the uses of statistical areas. The commenter also asked OMB to mandate that data provided for metropolitan and micropolitan statistical areas be displayed with data for the combined statistical area associated with those metropolitan or micropolitan statistical area components, and that data displayed at the metropolitan division level be displayed with data for the metropolitan statistical area of which the metropolitan division is a component. In addition, five commenters requested that OMB consider elimination of the prohibition against commingling in ranking combined statistical areas, on the one hand, and metropolitan statistical areas that do not belong to combined statistical areas, on the other hand.

One commenter asked for the inclusion of local opinion in the metropolitan and micropolitan statistical area qualification process, and another requested using local opinion in metropolitan division qualification. Another commenter more generally advocated some use of local opinion in the standards.

Sixteen commenters offered suggestions on an unidentified Federal program that appears to be unrelated to the metropolitan and micropolitan statistical areas program.

We have reviewed the out-of-scope comments and concluded that we could not accept suggestions that would alter the underlying concepts and framework of the 2000 standards, adhering instead to a more focused update. However, OMB, in consultation with the Census Bureau and the Review Committee, may give further consideration to the out-of-scope comments relating to the presentation of data when it updates the guidance on uses of the areas in its statistical areas bulletin.

C. OMB's Decisions Regarding Recommendations From the Metropolitan and Micropolitan Statistical Area Standards Review Committee Concerning Changes to the Standards for Defining Metropolitan and Micropolitan Statistical Areas

This section of the Notice provides information on the decisions OMB has made on the Review Committee's recommendations. In arriving at these decisions, we considered the public comment on the Review Committee's recommendations published in the Federal Register on February 12, 2009. OMB also benefited from the deliberations of the Review Committee as well as the research support provided by Census Bureau staff. We have relied upon and very much appreciate the technical and subject-matter expertise, insight, and dedication of the Review Committee members and the Census Bureau staff.

OMB presents below its decisions on the Review Committee's specific recommendations:

1. Recommendations Concerning Combined Statistical Areas

OMB accepts the Review Committee's recommendation to eliminate the use of local opinion in the qualification of combinations with employment interchange measures between 15 and 25. Adjacent core based statistical areas (CBSAs) should automatically qualify for combination if they possess an employment interchange measure of 15 or higher. OMB also accepts the recommendation to eliminate the use of local opinion in combined statistical area titling; each combined statistical area should be titled using the names of the two principal cities with the largest populations in the combined statistical area, as well as the name of the third-largest principal city, if present.

The 2000 standards provided for combined statistical areas to recognize ties between contiguous metropolitan and/or micropolitan statistical areas that are less intense than those captured by mergers, but still significant. (Mergers occur when adjacent CBSAs become a single CBSA because the central county or counties (as a group) of one CBSA qualify as outlying to the central county or counties (as a group) of the other CBSA.) These combinations were based on the employment interchange measure between two CBSAs, defined as the sum of the percentage of commuting from the smaller area to the larger area and the percentage of employment in the smaller area accounted for by workers residing in the larger area.

In reviewing the 2000 standards, OMB agrees with the Review Committee that combined statistical areas can serve as an important geographic tool for the Federal statistical data community. Under the current system—in which adjacent metropolitan and/or micropolitan statistical areas combine automatically if they have an employment interchange measure of 25 or more, while areas with an interchange measure of less than 25 but at least 15 qualify with the support of local opinion—the universe of combined statistical areas is heterogeneous and incomplete. This calls into question the comparability of the areas. Applying only statistical rules when delineating areas—the means by which the other statistical areas delineated by OMB currently qualify—minimizes ambiguity and maximizes the replicability, transparency, and integrity of the process. OMB agrees with the committee on applying only statistical rules, automatically combining all areas with the minimum employment interchange measure of 15.

Under the 2000 standards, local opinion also was used for determining titles for combined statistical areas. OMB agrees with the committee that just as the qualification of combined statistical areas should be based on the application of statistical rules, so too should combined statistical area titling. OMB agrees with the committee's recommendation for the elimination of local opinion from combined statistical area titling and instead titling combined statistical areas in essentially the same manner as their component metropolitan and or micropolitan statistical areas: The title of a combined statistical area should be based on the names of the two principal cities with the largest populations in the combination, as well as the name of the third-largest principal city, if present. To avoid a source of potential confusion, however, OMB also agrees with the committee's recommendation for dropping the name of the third-most-populous principal city from the title of a combined statistical area if the combined statistical area title duplicates that of one of its component CBSAs.

2. Recommendations Concerning Postcensal Updates

OMB accepts the Review Committee's recommendation that OMB: (1) Limit its yearly updates after the initial delineation based on the 2010 standards to the identification of new metropolitan and micropolitan statistical areas (and reflect certain changes to principal cities such as names and legal status) and (2) conduct a broader update in 2018 based on those aspects of delineation that can be performed using Census Bureau Population Estimates Program total population estimates as well as the 2011-2015 American Community Survey 5-year commuting and employment estimates.

For some purposes, frequent updates of the areas are desirable, but for other purposes stability of the inventory of areas has advantages.

OMB notes that the committee examined the criteria for statistical area updates in the 2000 standards as well as the application of those criteria. Annual postcensal updates of statistical areas since 2003 have been extensive and have included: (1) Qualification of new micropolitan statistical areas; (2) qualification of new metropolitan statistical areas; (3) qualification of new and expanded combined statistical areas, (4) qualification of new principal cities; (5) deletion of principal cities; and (6) changes in the titles of metropolitan statistical areas, micropolitan statistical areas, and metropolitan divisions, based on the addition and/or deletion of principal cities as well as changes in the relative population size rankings of principal cities.

OMB agrees with the Review Committee's observation that aspects of yearly updates can present potential difficulties to producers and users of metropolitan and micropolitan statistical area data, including the potentially considerable workload that yearly postcensal update titling and coding changes can pose for maintaining large databases. OMB supports a more limited yearly update, identifying only new metropolitan and micropolitan statistical areas. (The identification of a new metropolitan or micropolitan statistical area can lead to the creation of a new combined statistical area or the expansion of an existing combined statistical area.) OMB would continue to reflect changes to principal cities based on changes in their names and legal status. For example, if a principal city disincorporates or changes its name, that would be reflected in the yearly update of the inventory of principal cities, CBSA titles, and codes.

OMB agrees with the Review Committee's recommendation for a more comprehensive update of metropolitan and micropolitan and related statistical areas in 2018 based on those parts of delineation that can be updated using Census Bureau Population Estimates Program total population estimates and the 2011-2015 American Community Survey 5-year commuting and employment estimates. The urbanized areas and urban clusters used in the 2018 update will be those delineated with 2010 Census data, plus any urban areas delineated later through special censuses. The central counties of CBSAs identified on the basis of a 2010 Census population count, or on the basis of population estimates or a special census count in the case of postcensally delineated areas, would constitute the central counties for purposes of this set of area delineations.

3. Recommendation Concerning the Use of the Word “Definition”

OMB accepts the Review Committee's recommendation that OMB replace the word “definition” with the word “delineation” in the proposed 2010 standards.

During much of the history of the metropolitan and micropolitan statistical area program, the term “definition” has been used to refer to the boundaries or geographic makeup of an area (e.g., the definition of the Altoona, PA Metropolitan Statistical Area). While the program's use of the term has been careful and consistent, it is not intuitive for those first encountering the program.

OMB agrees with the committee that the program's use of the term “definition” occasionally has caused misunderstandings and accepts the committee's recommendation to replace “definition” with “delineation” to reference the geographic boundaries of the statistical areas.

D. 2010 Standards for Delineating Metropolitan and Micropolitan Statistical Areas and Key Terms

The Office of Management and Budget will use these standards to delineate Core Based Statistical Areas (CBSAs) beginning in 2013.

A CBSA is a geographic entity associated with at least one core of 10,000 or more population, plus adjacent territory that has a high degree of social and economic integration with the core as measured by commuting ties. The standards designate and delineate two categories of CBSAs: Metropolitan Statistical Areas and Micropolitan Statistical Areas.

The purpose of the Metropolitan and Micropolitan Statistical Area standards is to provide nationally consistent delineations for collecting, tabulating, and publishing Federal statistics for a set of geographic areas. The Office of Management and Budget establishes and maintains these areas solely for statistical purposes.

Metropolitan and Micropolitan Statistical Areas are not designed as a general-purpose geographic framework for nonstatistical activities or for use in program funding formulas. The CBSA classification is not an urban-rural classification; Metropolitan and Micropolitan Statistical Areas and many counties outside CBSAs contain both urban and rural populations.

CBSAs consist of counties and equivalent entities throughout the United States and Puerto Rico. In view of the importance of cities and towns in New England, a set of geographic areas similar in concept to the county-based CBSAs also will be delineated for that region using cities and towns. These New England City and Town Areas (NECTAs) are intended for use with statistical data, whenever feasible and appropriate, for New England. Data providers and users desiring areas delineated using a nationally consistent geographic building block should use the county-based CBSAs in New England.

The following criteria apply to both the nationwide county-based CBSAs and to NECTAs, with the exceptions of Sections 7 and 9 in which separate criteria are applied when identifying and titling divisions within NECTAs that contain at least one core of 2.5 million or more population. Wherever the word “county” or “counties” appears in the following criteria (except in Sections 7 and 9), the words “city and town” or “cities and towns” should be substituted, as appropriate, when delineating NECTAs. Commuting and employment estimates are derived from the Census Bureau's American Community Survey.

Section 1. Population Size Requirements for Qualification of Core Based Statistical Areas

Each CBSA must have a Census Bureau delineated urbanized area of at least 50,000 population or a Census Bureau delineated urban cluster of at least 10,000 population. (Urbanized areas and urban clusters are collectively referred to as “urban areas.”)

Section 2. Central Counties

The central county or counties of a CBSA are those counties that:

(a) Have at least 50 percent of their population in urban areas 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 of at least 10,000 population.

A central county is associated with the urbanized area or urban cluster that accounts for the largest portion of the county's population. The central counties associated with a particular urbanized area or urban cluster are grouped to form a single cluster of central counties for purposes of measuring commuting to and from potentially qualifying outlying counties.

Section 3. Outlying Counties

A county qualifies as an outlying county of a CBSA if it meets the following commuting requirements:

(a) At least 25 percent of the workers living in the county work in the central county or counties of the CBSA; or

(b) At least 25 percent of the employment in the county is accounted for by workers who reside in the central county or counties of the CBSA.

A county may be included in only one CBSA. If a county qualifies as a central county of one CBSA and as outlying in another, it falls within the CBSA in which it is a central county. A county that qualifies as outlying to multiple CBSAs falls within the CBSA with which it has the strongest commuting tie, as measured by either 3(a) or 3(b) above. The counties included in a CBSA must be contiguous; if a county is not contiguous with other counties in the CBSA, it will not fall within the CBSA.

Section 4. Merging of Adjacent Core Based Statistical Areas

Two adjacent CBSAs will merge to form one CBSA if the central county or counties (as a group) of one CBSA qualify as outlying to the central county or counties (as a group) of the other CBSA using the measures and thresholds stated in 3(a) and 3(b) above.

Section 5. Identification of Principal Cities

The Principal City (or Cities) of a CBSA will include:

(a) The largest incorporated place with a 2010 Census population of at least 10,000 in the CBSA or, if no incorporated place of at least 10,000 population is present in the CBSA, the largest incorporated place or census designated place in the CBSA; and

(b) Any additional incorporated place or census designated place with a 2010 Census 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 2010 Census population of at least 50,000, but less than 250,000, and in which the number of workers working in the place meets or exceeds the number of workers living in the place; and

(d) Any additional incorporated place or census designated place with a 2010 Census population of at least 10,000, but less than 50,000, and at least one-third the population size of the largest place, and in which the number of workers working in the place meets or exceeds the number of workers living in the place.

Section 6. Categories and Terminology

A CBSA is categorized based on the population of the largest urban area (urbanized area or urban cluster) within the CBSA. Categories of CBSAs are: Metropolitan Statistical Areas, based on urbanized areas of 50,000 or more population, and Micropolitan Statistical Areas, based on urban clusters of at least 10,000 population but less than 50,000 population. Counties that do not fall within CBSAs will represent “Outside Core Based Statistical Areas.”

A NECTA is categorized in a manner similar to a CBSA and is referred to as a Metropolitan NECTA or a Micropolitan NECTA.

Section 7. Divisions of Metropolitan Statistical Areas and New England City and Town Areas

(a) A Metropolitan Statistical Area containing a single urbanized area with a population of at least 2.5 million may be subdivided to form smaller groupings of counties referred to as Metropolitan Divisions. A county qualifies as a “main county” of a Metropolitan Division if 65 percent or more of workers living in the county also work within the county and the ratio of the number of workers working in the county to the number of workers living in the county is at least .75. A county qualifies as a “secondary county” if 50 percent or more, but less than 65 percent, of workers living in the county also work within the county and the ratio of the number of workers working in the county to the number of workers living in the county is at least 75.

A main county automatically serves as the basis for a Metropolitan Division. For a secondary county to qualify as the basis for forming a Metropolitan Division, it must join with either a contiguous secondary county or a contiguous main county with which it has the highest employment interchange measure of 15 or more. After all main counties and secondary counties are identified and grouped (if appropriate), each additional county that already has qualified for inclusion in the Metropolitan Statistical Area falls within the Metropolitan Division associated with the main/secondary county or counties with which the county at issue has the highest employment interchange measure. Counties in a Metropolitan Division must be contiguous.

(b) A NECTA containing a single urbanized area with a population of at least 2.5 million may be subdivided to form smaller groupings of cities and towns referred to as NECTA Divisions. A city or town will be a “main city or town” of a NECTA Division if it 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.

After all main cities and towns have been identified, each remaining city and town in the NECTA will fall within the NECTA Division associated with the city or town with which the one at issue has the highest employment interchange measure. Each NECTA Division must contain a total population of 100,000 or more. Cities and towns first assigned to areas with populations less than 100,000 will be assigned to the qualifying NECTA Division associated with the city or town with which the one at issue has the highest employment interchange measure. Cities and towns within a NECTA Division must be contiguous.

Section 8. Combining Adjacent Core Based Statistical Areas

(a) Any two adjacent CBSAs will form a Combined Statistical Area if the employment interchange measure between the two areas is at least 15.

(b) The CBSAs thus combined will also continue to be recognized as individual CBSAs within the Combined Statistical Area.

Section 9. Titles of Core Based Statistical Areas, Metropolitan Divisions, New England City and Town Divisions, and Combined Statistical Areas

(a) The title of a CBSA or NECTA will include the name of its Principal City with the largest 2010 Census population. If there are multiple Principal Cities, the names of the second-largest and (if present) third-largest Principal Cities will appear in the title in order of descending population size. If the Principal City with the largest 2010 Census population is a census designated place, the name of the largest incorporated place of at least 10,000 population that also is a Principal City will appear first in the title followed by the name of the census designated place. If the Principal City with the largest 2010 Census population is a census designated place, and there is no incorporated place of at least 10,000 population that also is a Principal City, the name of that census designated place Principal City will appear first in the title.

(b) The title of a Metropolitan Division will include the name of the Principal City with the largest 2010 Census population located in the Metropolitan Division. If there are multiple Principal Cities, the names of the second-largest and (if present) third-largest Principal Cities will appear in the title in order of descending population size. If there are no Principal Cities located in the Metropolitan Division, the title of the Metropolitan Division will use the names of up to three counties in order of descending 2010 Census population size.

(c) The title of a NECTA Division will include the name of the Principal City with the largest 2010 Census population located in the NECTA Division. If there are multiple Principal Cities, the names of the second-largest and (if present) third-largest Principal Cities will appear in the title in order of descending population size. If there are no Principal Cities located in the NECTA Division, the title of the NECTA Division will use the names of up to three cities or towns in descending 2010 Census population size.

(d) The title of a Combined Statistical Area will include the names of the two largest Principal Cities in the combination and the name of the third-largest Principal City, if present. If the Combined Statistical Area title duplicates that of one of its component CBSAs, the name of the third-most-populous Principal City will be dropped from the title of the Combined Statistical Area.

(e) Titles also will include the names of any State in which the area is located.

Section 10. Updating Schedule

(a) The Office of Management and Budget will delineate CBSAs in 2013 based on 2010 Census data and 2006-2010 American Community Survey 5-year estimates.

(b) In subsequent years, the Office of Management and Budget will designate a new Metropolitan Statistical Area if:

(1) A city that is outside any existing CBSA has a Census Bureau special census count of 10,000 to 49,999 population, or a population estimate of 10,000 to 49,999 for two consecutive years from the Census Bureau's Population Estimates Program, or

(2) A Census Bureau special census results in the delineation of an urban cluster of 10,000 to 49,999 population that is outside of any existing CBSA.

(c) Also in subsequent years, the Office of Management and Budget will designate a new Metropolitan Statistical Area if:

(1) A city that is outside any existing Metropolitan Statistical Area has a Census Bureau special census count of 50,000 or more population, or a population estimate of 50,000 or more for two consecutive years from the Census Bureau's Population Estimates Program, or

(2) A Census Bureau special census results in the delineation of a new urbanized area of 50,000 population or more that is outside of any existing Metropolitan Statistical Area.

(d) Outlying counties of CBSAs that qualify after the first delineation (in 2013) will qualify, according to the criteria in Section 3 above, on the basis of American Community Survey 5-year commuting estimates.

(e) The Office of Management and Budget will review the delineations of all existing CBSAs and related statistical areas in 2018 using 2011-2015 5-year commuting and employment estimates from the Census Bureau's American Community Survey. The urbanized areas and urban clusters used in these delineations will be those based on 2010 Census data or subsequent special censuses for which urban areas are created. The central counties of CBSAs identified on the basis of a 2010 Census population count, or on the basis of population estimates from the Census Bureau's Population Estimates Program or a special census count in the case of postcensally delineated areas, will constitute the central counties for purposes of the these area delineations. New CBSAs will be designated in 2018 on the basis of Census Bureau special census counts or population estimates as described above in Sections 10(b) and 10(c); outlying county qualification will be based on 5-year commuting estimates from the American Community Survey.

(f) Other aspects of the Metropolitan and Metropolitan Statistical Area and related statistical area delineations are not subject to change between decennial censuses.

Section 11. Definitions of Key Terms

Census designated place—A statistical geographic entity that is analogous to an incorporated place, delineated for the decennial census, consisting of a locally recognized, unincorporated concentration of population that is identified by name.

Central county—The county or counties of a Core Based Statistical Area containing a substantial portion of an urbanized area or urban cluster or both, and to and from which commuting is measured to determine qualification of outlying counties.

Combined Statistical Area—A geographic entity consisting of two or more adjacent Core Based Statistical Areas with employment interchange measures of at least 15.

Core—A densely settled concentration of population, comprising either an urbanized area (of 50,000 or more population) or an urban cluster (of 10,000 to 49,999 population) delineated by the Census Bureau, around which a Core Based Statistical Area is delineated.

Core Based Statistical Area (CBSA)—A statistical geographic entity consisting of the county or counties associated with at least one core (urbanized area or urban cluster) of at least 10,000 population, plus adjacent counties having a high degree of social and economic integration with the core as measured through commuting ties with the counties containing the core. Metropolitan and Micropolitan Statistical Areas are the two categories of Core Based Statistical Areas.

Delineation—The establishment of the boundary of a statistical area, or the boundary that results.

Employment interchange measure—A measure of ties between two adjacent entities. The employment interchange measure is the sum of the percentage of workers living in the smaller entity who work in the larger entity and the percentage of employment in the smaller entity that is accounted for by workers who reside in the larger entity.

Geographic building block—The geographic unit, such as a county, that constitutes the basic geographic component of a statistical area.

Main city or town—A city or town that acts as an employment center within a New England City and Town Area that has a core with a population of at least 2.5 million. A main city or town serves as the basis for delineating a New England City and Town Area Division.

Main county—A county that acts as an employment center within a Core Based Statistical Area that has a core with a population of at least 2.5 million. A main county serves as the basis for delineating a Metropolitan Division.

Metropolitan Division—A county or group of counties within a Core Based Statistical Area that contains an urbanized area with a population of at least 2.5 million. A Metropolitan Division consists of one or more main/secondary counties that represent an employment center or centers, plus adjacent counties associated with the main/secondary county or counties through commuting ties.

Metropolitan Statistical Area—A Core Based Statistical Area associated with at least one urbanized area that has a population of at least 50,000. The Metropolitan Statistical Area comprises the central county or counties containing the core, plus adjacent outlying counties having a high degree of social and economic integration with the central county or counties as measured through commuting.

Micropolitan Statistical Area—A Core Based Statistical Area associated with at least one urban cluster that has a population of at least 10,000, but less than 50,000. The Micropolitan Statistical Area comprises the central county or counties containing the core, plus adjacent outlying counties having a high degree of social and economic integration with the central county or counties as measured through commuting.

New England City and Town Area (NECTA)—A statistical geographic entity that is delineated using cities and towns as building blocks and that is conceptually similar to the Core Based Statistical Areas in New England (which are delineated using counties as building blocks).

New England City and Town Area (NECTA) Division—A city or town or group of cities and towns within a NECTA that contains an urbanized area with a population of at least 2.5 million. A NECTA Division consists of a main city or town that represents an employment center, plus adjacent cities and towns associated with the main city or town, or with other cities and towns that are in turn associated with the main city or town, through commuting ties.

Outlying county—A county that qualifies for inclusion in a Core Based Statistical Area on the basis of commuting ties with the Core Based Statistical Area's central county or counties.

Outside Core Based Statistical Areas—Counties that do not qualify for inclusion in a Core Based Statistical Area.

Principal City—The largest city of a Core Based Statistical Area, plus additional cities that meet specified statistical criteria.

Secondary county—A county that acts as an employment center in combination with a main county or another secondary county within a Core Based Statistical Area that has a core with a population of at least 2.5 million. A secondary county may serve as the basis for delineating a Metropolitan Division, but only when combined with a main county or another secondary county.

Urban area—The term used by the Census Bureau to refer collectively to urbanized areas and urban clusters.

Urban cluster—A statistical geographic entity delineated by the Census Bureau, consisting of densely settled census tracts and blocks and adjacent densely settled territory that together contain at least 2,500 people. For purposes of delineating Core Based Statistical Areas, only those urban clusters of 10,000 more population are considered.

Urbanized area—A statistical geographic entity delineated by the Census Bureau, consisting of densely settled census tracts and blocks and adjacent densely settled territory that together contain at least 50,000 people.