Geographic Concepts

The Local Area Unemployment Statistics (LAUS) program provides estimates for the following geographic areas:

  1. census regions and divisions;
  2. states, the District of Columbia, and Puerto Rico;
  3. federal statistical areas—metropolitan areas, metropolitan divisions, micropolitan areas, and combined areas;
  4. small labor market areas;
  5. counties and county equivalents;
  6. cities of 25,000 population or more;
  7. all cities and towns in New England, regardless of population; and
  8. parts of cities listed in (6) above which cross county boundaries.

Standard geographic area definitions based on existing political divisions are used by the LAUS program to determine the specific areas for which estimates are generated. These same definitions are used by other federal and state agencies, enabling comparison and tabulation of data across programs. Standardized definitions also increase the availability of input data for the LAUS program from other statistical or administrative programs.

Local geographic area designations vary across the United States. For example, parishes in Louisiana and boroughs in Alaska are equivalent to counties; independent cities in Maryland, Missouri, Nevada, and Virginia are considered equivalent to counties; and cities and towns in New England are used instead of counties, since counties in New England historically have little geopolitical significance.

Federal Statistical Areas

Standard delineations of areas for federal statistical purposes are established by the Office of Management and Budget (OMB). Updates to the standards for delineating areas occur each decade following the census. For the standards used by OMB to revise federal statistical areas following the 2010 Census, see the Federal Register notice dated June 28, 2010. The updated federal statistical areas based on the application of these standards to population data from the 2010 Census and commutation data from the American Community Survey were issued on February 28, 2013, through OMB Bulletin No. 13-01, Revised Delineations of Metropolitan Statistical Areas, Micropolitan Statistical Areas, and Combined Statistical Areas, and Guidance on Uses of the Delineations of These Areas.

Relative to the Census 2000-based delineations, the number of 2010-based metropolitan areas in the U.S. and Puerto Rico increased from 380 to 394, while the number of micropolitan areas decreased from 590 to 546. The number of metropolitan divisions increased from 34 to 38, and the number of combined areas increased from 134 to 171. These counts reflect the LAUS program's use of New England City and Town Areas (NECTAs) for the six New England states, which OMB again delineated as an alternative equivalent to the county-based delineations for that part of the country.

Small Labor Market Areas

Labor market areas (LMAs) are an exhaustive level of substate geography published by the LAUS program. The metropolitan and micropolitan areas delineated by OMB are "major" LMAs for LAUS purposes. The balance of the U.S. is grouped into "small" LMAs, consisting of one or more counties or county equivalents. The LAUS program redefines small LMAs after each decennial census. The current small LMAs are based on commutation data from the American Community Survey 5-year dataset for 2006-10, the same source of the commutation data used by OMB for its 2010-based metropolitan and micropolitan area delineations.

Broadly, a LMA is an economically integrated geographic area within which individuals can reside and find employment within a reasonable distance or can readily change employment without changing their place of residence. In addition, LMAs are non-overlapping and geographically exhaustive. Since these areas are based on the degree of economic integration as measured by commuting flows without regard to state boundaries, interstate LMAs exist. LMAs in New England are composed of cities and towns rather than counties.

The following criteria were used to designate small LMAs following the 2010 Census:

  1. Worker flows were examined, and counties combined into one small LMA if either or both of the following conditions were met:
    • At least 25 percent of the employed residents of one county commuted to work in another county
    • At least 25 percent of the employment (persons working) in one county were accounted for by workers commuting from another county.
  2. Small LMAs, as is the case with metropolitan and micropolitan areas, are required to be contiguous. First, counties were combined based on the commutation criteria. Then, potential multi-county small LMAs were checked for contiguity. Noncontiguous portions of potential small LMAs were considered separately. If the noncontiguous area contained more than one county, it was reevaluated using (1) above. If the noncontiguous area consisted of a single county, it was designated as a separate small LMA.
  3. Subsequent to the verification of contiguity described in (2) above, commuting flows between adjacent small LMAs were evaluated. Those areas for which the measures and thresholds specified in (1) above were met merged to form one small LMA. This procedure was limited to one iteration, as was the case for metropolitan and micropolitan area delineation under the 2010-based OMB standards.
  4. For the New England city and town-based small LMAs, due to the large number of small cities and towns, residual cities and towns were added to contiguous small LMAs based on commuting flows and/or other economic ties. If, after applying the commutation criteria, a city or town had been identified as an individual small LMA, the city or town may have been added to a contiguous small LMA, especially if the city or town was extremely small. Fourteen towns that were isolated between the metropolitan and/or micropolitan NECTAs delineated by OMB were not defined within labor market areas.

Naming Conventions:  Single-county small LMA names include the full county name, followed by the state abbreviation, such as "Hill County, TX." Multi-county small LMA names consist of not more than three county names, in descending order of population, followed by the state abbreviation and the term "LMA," as in "Rockbridge-Lexington-Buena Vista, VA LMA."

In the case of interstate small LMAs, state abbreviations were sequenced according to the population sizes of the intrastate parts. That is, the state with the largest population share among the parts of the area is listed first, and so on, as in "Gogebic-Iron, MI-WI LMA."

Other Defined Areas

In addition to LAUS areas based on standard geographic classifications, several nonstandard areas are defined. Where LMAs cross state lines, estimates for each intrastate part of the interstate LMA are created as a necessity of the LAUS estimation procedure. Similarly, cities that are located in more than one county must have estimates created for the city parts in each county.

 

Last Modified Date: April 21, 2015