This page is about definitions and long term context for the BLS unemployment numbers.
11 Jul 2009.
Most reported unemployment statistics are from the Bureau of Labor Statistics in the Department of Labor. All the BLS unemployment data are from the Current Population Survey, a monthly survey of a probability sample of approximately 60,000 households, conducted by the Bureau of the Census for the BLS. Data are collected by personal and telephone interviews. Response is voluntary, but only about 4% refuse. Roughly speaking, the BLS divides the population into the “Employed” (E), the “Unemployed” (U; must have looked for a job in the last four weeks), the “Marginally attached” (M; looking for a job but not in the last 4 weeks), those not looking for a job at all (N), and the institutionalized. The unemployment rate usually reported is U-3, including just the Unemployed (U / E + U). There is also a broader measure of unemployment, U-6, which includes the Unemployed, those working part-time for economic reasons (i.e. wanting full-time ; PTER), and the Marginally attached; these are all the people who are looking for full-time work but are unable to find it (U + PTER + M / E + U + M). There is one other statistic of interest, the “Not employed”. This includes those who are not looking for work (NLFW; so U + M + NLFW / E + U + M + NLFW). The survey questions and the definitions have changed over time. Probably the official unemployment rate has been pretty stable over time but, strictly speaking, current data is only comparable to data back to Jan 1994.
Entries below covered through 3 Jul 2008:
Oct 1995. Monthly Labor Review, scanned paper on BLS website.
http://www.bls.gov/opub/mlr/1995/10/art3full.pdf
“BLS introduces new range of alternative unemployment measures. John E. Bregger and Steven E. Haugen”
“since the inception of the survey in 1940, only relatively minor changes have been made to the official definition of unemployment. (Definitionally, it was not changed at all, except for elimination of a small group of persons, namely those who volunteered the information that they were waiting to start a new job within 30 days, most of whom undoubtedly meet the jobseeking tests in any case. There were, however, changes in the wording of nearly all the questions – particularly as regards persons on layoff – that affected the underlying data in limited ways) … Most analysts monitor unemployment because of its role as a cyclical indicator … represents the degree to which available labor resources are not being utilized in the economy … The [January] 1994 redesign … a number of changes made to the questionnaire and overall survey methodology affected the measure of employment, unemployment, and persons not in the labor force; and second, several definitional changes were introduced. … employed part-time for economic reasons. The figure was sharply lower under the redesigned survey, as respondents were explicitly asked about their desire and availability for full-time work. … Considerable tightening of the requirements for discouraged worker status reduced the number of persons so classified by about half. … Effects on indicator U-5 [which became U-3 in the new numbering system] … the official unemployment rate … marginally higher - an estimated 0.2 percentage point - under the redesigned CPS … effects on indicator U-7 [the most comprehensive, roughly corresponding to U-6 now] … markedly higher in the old survey than under the new one.”
[U-5b is the pre-1994 equivalent to the 1994-and-after U-3, i.e. the official unemployment rate]
17 Apr 2003. BLS Handbook, on the BLS website.
http://www.bls.gov/opub/hom/homch1_b.htm
“Labor Force Data Derived from the Current Population Survey”
“Description of the Survey
The CPS collects information on the labor force status of the civilian noninstitutional population 15 years of age and older, although labor force estimates are reported only for those 16 and older. Persons under 16 years of age are excluded from the official estimates because child labor laws, compulsory school attendance, and general social custom in the United States severely limit the types and amount of work that these children can do. Persons on active duty in the U.S. Armed Forces are excluded from coverage. The institutional population, which also is excluded from coverage, consists of residents of penal and mental institutions and homes for the aged and infirm.
The CPS is collected each month from a probability sample of approximately 60,000 households. Respondents are assured that all information obtained is completely confidential and is used only for the purpose of statistical analysis. Although the survey is conducted on a strictly voluntary basis, refusals to cooperate amount to only about 4 percent each month. (Another 3 to 4 percent of eligible households are not interviewed because of other failures to make contact.)
A calendar week was selected as the survey reference period because the period used must be short enough so that the data obtained are “current,” but not so short that such occurrences as holidays or bad weather might cause erratic fluctuations in the information obtained. In addition, the reference period should not be so long that it challenges the recall of the respondent. A calendar week fulfills these conditions. Since July 1955, the calendar week, Sunday through Saturday, that includes the 12th day of the month has been defined as the reference week. The actual survey is conducted during the following week, the week containing the 19th day of the month.”
27 Jul 2004. BLS web site
http://www.bls.gov/cps/cps_over.htm#overview
“The Current Population Survey, a monthly household survey conducted by the Bureau of the Census for the Bureau of Labor Statistics, provides a comprehensive body of information on the employment and unemployment experience of the Nation's population, classified by age, sex, race, and a variety of other characteristics. … data are collected by personal and telephone interviews. Basic labor force data are gathered monthly; data on special topics are gathered in periodic supplements.”
3 Jul 2008. BLS website, Glossary page.
http://www.bls.gov/bls/glossary.htm
”
”
12 May 2009. The Economic Populist.
http://www.economicpopulist.org/content/u3-and-u6-unemployment-during-great-depression
[Bottom line: stats are not directly comparable, but unemployment today is nowhere near as bad as it was in the depression.]
19 Jun 2009. Congressional Research Service.
http://assets.opencrs.com/rpts/R40655_20090619.pdf
“The Labor Market during the Great Depression and the Current Recession. Linda Levine”
“A good deal of commentary has addressed similarities between the recession that began in December 2007 and the Great Depression. Comparisons between the two have extended beyond conditions in financial markets to conditions in the labor market. The analogy appears to be fueled by projections that the unemployment rate could reach double digits in the coming months.
Little if any comparative labor market research has been undertaken, however. To address the situation, this report analyzes the experiences of workers during the 1930s, which encompassed the almost five years of the Great Depression. Because it was a period very distant and different from today, the report devotes considerable time to examining the employment and unemployment measures then available. The report ends by comparing the labor market conditions of the 1930s with those encountered by workers thus far during the nation’s eleventh recession of the post-World War II period. …
[It is very difficult to compare unemployment rates, but NFP did exist at the time, and shows that the great depression really was much worse than any recession since:]
Employers cut the total number of jobs on their payrolls much more deeply during the Great Depression than they have thus far in the latest recession. Between 1929 and 1933, employment on nonfarm payrolls fell by 24.3%, compared to 4.3% thus far in the recession.”