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Technical Note
The data in this release were collected through a supplement to the
September 2008 Current Population Survey (CPS). The CPS--a monthly
survey of about 60,000 households conducted by the U.S. Census Bureau
for the Bureau of Labor Statistics--focuses on obtaining information on
employment and unemployment among the nation's civilian noninstitutional
population age 16 and over. The purpose of this supplement to the CPS
was to obtain information on the incidence of volunteering and the
characteristics of volunteers in the United States.
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.
Reliability of the estimates
Statistics based on the CPS are subject to both sampling and non-
sampling error. When a sample, rather than the entire population, is
surveyed, there is a chance that the sample estimates may 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-percent 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, inability to obtain information for all
respondents in the sample, 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 CPS data and for
information on estimating standard errors, see the Household Data
Section of the "Explanatory Notes and Estimates of Error" at
http://www.bls.gov/cps/eetech_methods.pdf.
The Census Bureau introduces adjustments to the population controls
for the CPS as part of its annual update of population estimates. The
2003 adjustment resulted in an increase to the estimates for all
population categories. This increase was partly offset by downward
adjustments in 2004, 2005, 2006, and 2008. The 2007 adjustment was in
the upward direction. Consequently, estimated levels of volunteers for
September 2003, 2004, 2005, 2006, 2007, and 2008 are not strictly com-
parable with one another, or with estimated levels for September
2002. These adjustments to the levels, however, should have had only
negligible effects on the volunteer rates. In addition to the population
control adjustments, new questions on race and ethnicity were introduced
into the CPS in January 2003. For a discussion of the changes introduced
into the CPS in January 2003, see "Revisions to the Current Population
Survey Effective in January 2003," in the February 2003 issue of Employ-
ment and Earnings, at http://www.bls.gov/cps/rvcps03.pdf. For a discus-
sion of the changes introduced in January 2004, see "Adjustments to House-
hold Survey Population Estimates in January 2004," in the February 2004
issue of Employment and Earnings, at http://www.bls.gov/cps/cps04adj.pdf.
For a discussion of the changes introduced in January 2005, see "Adjust-
ments to Household Survey Population Estimates in January 2005," in the
February 2005 issue of Employment and Earnings, at http://www.bls.gov/
cps/cps05adj.pdf. For a discussion of the changes introduced in January
2006, see "Adjustments to Household Survey Population Estimates in Jan-
uary 2006," in the February 2006 issue of Employment and Earnings, at
http://www.bls.gov/cps/cps06adj.pdf. For a discussion of the changes
introduced in January 2007, see "Adjustments to Household Survey Popu-
lation Estimates in January 2007," in the February 2007 issue of Employ-
ment and Earnings, at http://www.bls.gov/cps/cps07adj.pdf. For a dis-
cussion of the changes introduced in January 2008, see "Adjustments to
Household Survey Population Estimates in January 2008," in the February
2008 issue of Employment and Earnings Online, available on the BLS Web
site at http://www.bls.gov/cps/cps08adj.pdf.
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Volunteer questions and concepts
In the September 2008 supplement, questions on volunteer activities
were asked of all households. Efforts were made to have household
members answer the volunteer questions for themselves. (Generally, one
member of the household answers all the questions in the CPS on behalf
of the entire household.) Self-response was considered important for
the volunteer supplement because research indicated that self-respond-
ents could more easily answer questions on the characteristics of the
volunteer activity. About 68.2 percent of the responses were self-
reports.
The survey was introduced as follows: "This month, we are interested
in volunteer activities, that is, activities for which people are not
paid, except perhaps expenses. We only want you to include volunteer
activities that you did through or for an organization, even if you only
did them once in a while."
Following this introduction, respondents were asked the first supple-
ment question: "Since September 1st of last year, have you done any
volunteer activities through or for an organization?"
If respondents did not answer "yes" to the first question, they were
asked the following question: "Sometimes people don't think of activi-
ties they do infrequently or activities they do for children's schools
or youth organizations as volunteer activities. Since September 1st of
last year, have you done any of these types of volunteer activities?"
Respondents were considered volunteers if they answered "yes" to
either of these questions. This is the same method of identifying
volunteers as was used in each of the six prior supplements.
Respondents classified as volunteers were asked further questions
about the number and type of organizations for which they volunteered,
total hours spent volunteering, how they became involved with the main
organization for which they volunteered, the type of activities they
performed for the main organization, and what their main activity was.
The reference period for the questions on volunteering was about 1
year, from September 1, 2007, through the survey week in September 2008.
The reference period for other characteristics--such as labor force
status, educational attainment, and marital status--refer to the survey
reference week in September 2008. It is possible that these character-
istics were different at the time volunteer activities were performed.
One new question was added to the 2008 survey to determine whether or
not respondents had donated money, assets, or property with a combined
value of more than $25 to charitable or religious organizations in the
past 12 months. Two questions asked in the 2007 supplement were removed
in 2008. These questions asked how often respondents who had attended
public meetings or who had worked with others in their neighborhood to
fix a problem did so.
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Definitions
Volunteers are persons who performed unpaid volunteer activities at
any point from September 1, 2007, through the survey period in September
2008. The count of volunteers only includes persons who volunteered
through or for an organization; the figures do not include persons who
volunteered in a more informal manner. For example, a woman who taught
acting to children through a local theater would be considered a volun-
teer. However, a woman who, on her own, organized softball games for
the children in her neighborhood would not be counted as a volunteer
for the purpose of this survey.
Organizations are associations, societies, or groups of people who
share a common interest. Examples include churches, youth groups, and
civic organizations. For the purpose of this study, organizations are
grouped into eight major categories, including religious, youth, and
social or community service organizations. (See table 4.)
In the 2005 survey, one organization category, immigrant/refugee
assistance, was added to the questionnaire as a possible response.
Responses that were collected in this category may have been distributed
over at least six of the major organization categories in previous
years. For this reason, the addition of the new response category
created a break in the comparability of organizations between 2005 and
prior years. Because few people reported volunteering for immigrant/
refugee assistance organizations and because the group was not a de-
finite subset of any of the major organization categories, those
persons who did report that they volunteered for immigrant/refugee
assistance organizations were placed in the "other" group.
The main organization is the organization for which the volunteer
worked the most hours during the year. If a respondent volunteered for
only one organization, it was considered the main organization, even if
exact hours were not obtained.
In order to identify the type of main organization, respondents
provided information about the organization and, for those who
volunteered for more than one organization, annual hours worked for
each. Some respondents did not provide the information necessary to
determine the main organization. For these respondents, the follow-up
questions on activities and how they became involved with the main
organization asked them to report on the organization for which they
think they spent the most time volunteering.
Activities are the specific tasks the volunteer did for an organi-
zation. Examples include tutoring, fundraising, and serving food.
The activity categories were modified in 2005, thus creating a break in
the comparability of activities between 2005 and prior years.
In 2006, a new question was added that asked respondents on which of
the activities they mentioned they spent the most time. Previously,
respondents reported all of the activities they did for their main
organization. The new question identified which of them was the main
activity for the main organization.
