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Technical Note
The estimates in this release are obtained from the Current Population
Survey (CPS), which provides basic information on the labor force, employ-
ment, and unemployment. The survey is conducted monthly for the Bureau of
Labor Statistics by the U.S. Census Bureau from a scientifically selected
national sample of about 60,000 households.
Most of the data in this release are annual averages for 2007, compiled
from the results of the monthly survey. Some of the data, such as those
related to service-connected disability and Reserve or National Guard status,
are from special questions asked as part of the latest biennial veterans sup-
plement to the CPS, which was conducted in August 2007. The supplement was
co-sponsored by the U.S. Department of Veterans Affairs and by the U.S.
Department of Labor's Veterans’ Employment and Training Service. Questions
were asked of persons 17 years of age and older regarding their prior service
in the U.S. Armed Forces. Data are tabulated for persons 18 years of age and
older.
Information in this release will be made available to sensory impaired
individuals upon request. Voice phone: (202) 691-5200; TDD message referral
phone number: 1-800-877-8339.
Definitions
The definitions underlying the data in this release are as follows: Veterans
are men and women who previously served on active duty in the U.S. Armed Forces.
Members of the Reserve and National Guard are counted as veterans if they had
ever been called to active duty. Persons who are on active duty at the time of
the survey are outside the scope of the survey and thus not in the estimates shown
here, as are persons who reside in institutions, such as nursing homes and prisons.
Nonveterans are men and women who never served on active duty in the U.S. Armed
Forces.
World War II, Korean War, Vietnam-era, and Gulf War-era veterans are men and
women who served in the Armed Forces during these periods, regardless of where they
served. Veterans who served in more than one wartime period are classified in the
most recent one.
Veterans of other service periods are men and women who served in the Armed Forces
at any time other than World War II, the Korean War, the Vietnam era, or the Gulf
War era. Although U.S. Armed Forces were engaged in several armed conflicts during
other service periods, these conflicts were more limited in scope and included a
smaller proportion of the Armed Forces than the selected wartime periods. Veterans
who served during one of the selected wartime periods and during another period are
classified in the wartime period.
Veteran status is obtained from responses to the question, "Did you ever serve on
active duty in the U.S. Armed Forces?"
Period of service is obtained from answers to the question asked of veterans, "When
did you serve on active duty in the U.S. Armed Forces?" The following service periods
are identified:
Gulf War era II -- September 2001-present
Gulf War era I -- August 1990-August 2001
May 1975-July 1990
Vietnam era -- August 1964-April 1975
February 1955-July 1964
Korean War -- July 1950-January 1955
January 1947-June 1950
World War II -- December 1941-December 1946
November 1941 or earlier
Period-of-service definitions are modified occasionally to reflect changes in law,
regulations, and program needs of the survey sponsors.
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Presence of service-connected disability is provided by answers to the question,
"Has the Department of Veterans Affairs (VA) or Department of Defense (DoD) deter-
mined that you have a service-connected disability, that is, a health condition or
impairment caused or made worse by any of your military service?"
Service-connected disability rating is based on answers to the question, "What
is your current service-connected disability rating?" Answers can range from 0 to
100 percent, in increments of 10 percentage points. Ratings are determined by the
VA or DoD from a rating schedule published in the Code of Federal Regulations,
Title 38, "Pensions, Bonuses, and Veterans' Relief," Part 4--"Schedule for Rating
Disabilities." The rating schedule is "primarily a guide in the evaluation of dis-
ability resulting from all types of diseases and injuries encountered as a result of
or incident to military service. The percentage ratings represent, as far as can
practicably be determined, the average impairment in earning capacity resulting from
such diseases and injuries and their residual conditions in civil occupations."
Part 4 contains a listing of hundreds of possible disorders and assigns ratings of
0 through 100 percent in steps of 10 percent for each, with instructions for rating
multiple disorders.
Reserve or National Guard status is obtained from answers to two questions. Gulf
War-era veterans were asked: "Was any of your active service the result of a call-up
from the Reserve or National Guard?" If the answer was no, they were asked, "Have you
ever been a member of the Reserve or National Guard?" A ‘yes’ response to either ques-
tion classified persons as "Current or past member of the Reserve or National Guard."
A ‘no’ response to the latter question classified persons as "Never a member of the
Reserve or National Guard." These questions were asked only of Gulf War-era veterans.
Reliability of the estimates
Statistics based on the CPS are subject to both sampling and nonsampling error.
When a sample, rather than the entire population, is surveyed, there is a chance that
the sample estimates will differ from the "true" population values they represent.
The exact difference, or sampling error, varies depending on the particular sample
selected, and this variability is measured by the standard error of the estimate.
There is about a 90-percent chance, or level of confidence, that an estimate based on
a sample will differ by no more than 1.6 standard errors from the "true" population
value because of sampling error. BLS analyses are generally conducted at the 90-per-
cent level of confidence.
The CPS data also are affected by nonsampling error. Nonsampling error can occur
for many reasons, including the failure to sample a segment of the population, the
inability to obtain information for all respondents in the sample, the inability or
unwillingness of respondents to provide correct information, and errors made in the
collection or processing of the data.
For a full discussion of the reliability of data from the CPS and information on
estimating standard errors, see the explanatory note for the household survey online
at http://www.bls.gov/cps/eetech_methods.pdf.
Bureau of Labor Statistics
