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Technical Note
This release presents labor force and unemployment data from the
Local Area Unemployment Statistics (LAUS) program (tables 1 and 2) for
369 metropolitan statistical areas and metropolitan New England City and
Town Areas (NECTAs), plus 8 areas in Puerto Rico. Estimates for 34
metropolitan and NECTA divisions also are presented. Nonfarm payroll
employment estimates from the Current Employment Statistics (CES)
program (tables 3 and 4) are provided for most of the same areas. State
estimates were previously published in the news release, Regional and
State Employment and Unemployment, and are republished in this release
for ease of reference. The LAUS and CES programs are both federal-state
cooperative endeavors.
Labor force and unemployment--from the LAUS program
Definitions. The labor force and unemployment data are based on
the same concepts and definitions as those used for the official na-
tional estimates obtained from the Current Population Survey (CPS), a
sample survey of households that is conducted for the Bureau of Labor
Statistics (BLS) by the U.S. Census Bureau. The LAUS program measures
employment and unemployment on a place-of-residence basis. The universe
for each is the civilian noninstitutional population 16 years of age and
over. Employed persons are those who did any work at all for pay or
profit in the reference week (the week including the 12th of the month)
or worked 15 hours or more without pay in a family business or farm,
plus those not working who had a job from which they were temporarily
absent, whether or not paid, for such reasons as labor-management
dispute, illness, or vacation. Unemployed persons are those who were
not employed during the reference week (based on the definition above),
had actively looked for a job sometime in the 4-week period ending with
the reference week, and were currently available for work; persons on
layoff expecting recall need not be looking for work to be counted as
unemployed. The labor force is the sum of employed and unemployed
persons. The unemployment rate is the number of unemployed as a percent
of the labor force.
Method of estimation. Estimates for states, the District of
Columbia, the Los Angeles-Long Beach-Glendale metropolitan division,
and New York City are produced using time-series models with real-time
benchmarking to national CPS totals. Model-based estimation was
extended to the following areas and their respective balances of state
in 2005: the Chicago-Naperville-Joliet, IL Metropolitan Division;
Cleveland-Elyria-Mentor, OH Metropolitan Statistical Area; Detroit-
Warren-Livonia, MI Metropolitan Statistical Area; Miami-Miami Beach-
Kendall, FL Metropolitan Division; New Orleans-Metairie-Kenner, LA
Metropolitan Statistical Area; and Seattle-Bellevue-Everett, WA
Metropolitan Division. (Model-based estimation of the New Orleans-
Metairie-Kenner metropolitan area was suspended following Hurricane
Katrina; the indirect estimation methods described below will be used
for this area until further notice.) Modeling improves the statistical
basis of the estimation for these areas and provides important tools for
analysis, such as measures of errors and seasonally adjusted series.
For all other substate areas in this release, estimates are prepared
through indirect estimation procedures using a building-block approach.
Employment estimates, which are based largely on "place of work"
estimates from the CES program, are adjusted to refer to place of
residence as used in the CPS. Unemployment estimates are aggregates of
persons previously employed in industries covered by state unemployment
insurance (UI) laws and entrants to the labor force data from the CPS.
The substate estimates of employment and unemployment, which geograph-
ically exhaust the entire state, are adjusted proportionally to ensure
that they add to the independently estimated state or balance-of-
state totals. A detailed description of the estimation procedures is
available from BLS upon request.
Annual revisions. Labor force and unemployment data shown for the
prior year reflect adjustments made at the end of each year, usually
implemented with January estimates. The adjusted model-based estimates
reflect updated population data from the U.S. Census Bureau, any
revisions in the other data sources, and model reestimation. All
substate estimates are reestimated and adjusted to add to the revised
model-based estimates.
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Employment--from the CES program
Definitions. Employment data refer to persons on establishment
payrolls who receive pay for any part of the pay period that includes
the 12th of the month. Persons are counted at their place of work
rather than at their place of residence; those appearing on more than
one payroll are counted on each payroll. Industries are classified on
the basis of their principal activity in accordance with the 2007
version of the North American Industry Classification System.
Method of estimation. The employment data are estimated using a
"link relative" technique in which a ratio (link relative) of current-
month employment to that of the previous month is computed from a
sample of establishments reporting for both months. The estimates of
employment for the current month are obtained by multiplying the
estimates for the previous month by these ratios. Small-domain models
are used as the official estimators for the approximately 39 percent of
CES published series which have insufficient sample for direct sample-
based estimates.
Annual revisions. Employment estimates are adjusted annually to a
complete count of jobs, called benchmarks, derived principally from tax
reports that are submitted by employers who are covered under state
unemployment insurance (UI) laws. The benchmark information is used to
adjust the monthly estimates between the new benchmark and the preceding
one and also to establish the level of employment for the new benchmark
month. Thus, the benchmarking process establishes the level of employment,
and the sample is used to measure the month-to-month changes in the level
for the subsequent months.
Reliability of the estimates
The estimates presented in this release are based on sample surveys,
administrative data, and modeling and, thus, are subject to sampling
and other types of errors. Sampling error is a measure of sampling
variability--that is, variation that occurs by chance because a sample
rather than the entire population is surveyed. Survey data also are
subject to nonsampling errors, such as those which can be introduced
into the data collection and processing operations. Estimates not
directly derived from sample surveys are subject to additional errors
resulting from the particular estimation processes used. The sums of
individual items may not always equal the totals shown in the same
tables because of rounding. Unemployment rates are computed from
unrounded data and thus may differ slightly from rates computed using
the rounded data displayed in the tables.
Labor force and unemployment estimates. Model-based error measures
are available for states on the BLS Web site at http://www.bls.gov/lau/
lastderr.htm. Measures of nonsampling error are not available, but ad-
ditional information on the subject is provided in Employment and Earn-
ings Online at http://www.bls.gov/opub/ee/home.htm.
Employment estimates. Measures of sampling error for state CES data
at the supersector level and for metropolitan area CES data at the
total nonfarm level are available on the BLS Web site at http://www.bls.
gov/sae/790stderr.htm. Information on recent benchmark revisions for
states is available at http://www.bls.gov/sae/.
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Area definitions
The substate area data published in this release reflect the
standards and definitions established by the U.S. Office of Management
and Budget on November 20, 2007. Data reflect New England City and Town
Area (NECTA) definitions, rather than county-based definitions, in the
six New England States. A detailed list of the geographic definitions
is available on the Internet at http:// www.bls.gov/lau/lausmsa.htm.
Additional information
More complete information on the technical procedures used to develop
these estimates and additional data appear in Employment and Earnings
Online.
Estimates of unadjusted and seasonally adjusted labor force and
unemployment data for states, census regions and divisions, and seven
substate areas are available in the news release, Regional and State
Employment and Unemployment. Estimates of labor force and unemployment
for all states, metropolitan areas, labor market areas, counties, cities
with a population of 25,000 or more, and other areas used in the
administration of various federal economic assistance pro-grams are
available on the BLS Web site at http://www.bls.gov/lau/. Employment
data from the CES program are available at http://www.bls.gov/sae/.
Information in this release will be made available to sensory
impaired individuals upon request. Voice phone: (202) 691-5200; TDD
message referral phone: 1-800-877-8339.
Bureau of Labor Statistics
