Information about http://www.bls.gov/web/ces_cps_trends.pdf
…
Tags: benchmark revisions, bureau of labor, bureau of labor statistics, cps, data users, employment levels, employment situation, employment statistics, employment trends, household survey, household surveys, major features, measurement issues, methodologies, population control, population survey, summary comparison, survey estimates, survey population, website overview,Pages: 16
Language: english
Created: Thu Sep 4 14:22:04 2008
Display cached document
Page 1
Page 2
Page 3
Page 4
Page 5
Page 6
Page 7
Page 8
Page 9
Page 10
Page 11
Page 12
Page 13
Page 14
Page 15
Page 16
September 5, 2008
Employment from the BLS household and payroll surveys:
summary of recent trends
This report is updated monthly in conjunction with the release of the Employment Situation;
the release dates are available on the BLS website.
Overview
The Bureau of Labor Statistics (BLS) has two monthly surveys that measure employment levels and
trends: the Current Population Survey (CPS), also known as the household survey, and the Current
Employment Statistics (CES) survey, also known as the payroll or establishment survey.
Estimates from both surveys are published in the "Employment Situation" news release each month.
The household and payroll surveys use different definitions of employment and distinct survey and
estimation methods. To help data users better understand the differences in the surveys' employment
measures and divergences that sometimes occur in their trends, the following information is provided.
Summary comparison of household and payroll survey concepts, definitions, and methodologies
Employment trends as measured by the payroll and household surveys
Possible causes of differences in employment trends
Summary of recent changes made to each survey:
Population control adjustments to the household survey
Benchmark revisions to the payroll survey
1
September 5, 2008
Summary comparison of household and payroll survey concepts, definitions, and
methodologies
Major features and distinctions of the two surveys are compared below in Box 1. Additional
information on the methodologies of the two surveys can be found in the Quick Guide to Methods and
Measurement Issues on the BLS website.
Box 1. How the household and payroll surveys compare
Comparison by: Household Survey (CPS) Payroll Survey (CES)
Universe Civilian noninstitutional Nonfarm wage and salary
population age 16 and over jobs
Type of survey Monthly sample survey of Monthly sample survey of
approximately 60,000 about 160,000 businesses
households and government agencies
covering approximately
400,000 establishments
Major outputs Labor force, employment, Employment, hours, and
unemployment, and associated earnings with significant
rates with significant industry and geographic
demographic detail detail
Reference period Calendar week that includes Employer pay period that
the 12th of the month includes the 12th of the
month (could be weekly,
biweekly, monthly or other)
Employment concept Estimate of employed persons Estimate of jobs
(multiple jobholders are (multiple jobholders counted
counted only once) for each nonfarm payroll job)
Employment definition Includes the unincorporated Excludes all of the groups
differences self employed, unpaid family listed at left, except for the
workers, agriculture and logging component of
related workers, private agriculture and related
household workers, and industries
workers absent without pay
Continued on next page
2
September 5, 2008
Comparison by: Household Survey (CPS) Payroll Survey (CES)
Size of over-the-month +436,000¹ +104,000
change in employment
required for a statistically
significant movement
Benchmark adjustments to No direct benchmark for Employment benchmarked
survey results employment. Adjustments to annually to employment
underlying population base counts derived primarily
revised annually to intercensal from Unemployment
estimates, and every 10 years Insurance (UI) tax records
to the decennial census
¹ This figure is updated periodically to incorporate more current data. The latest update (in March 2005)
also included a correction in the program used to calculate it. For more information, see "Updates and
adjustments to Current Population Survey standard errors" at
http://www.bls.gov/cps/cps_err_update.htm.
3
September 5, 2008
Employment trends as measured by the household and payroll surveys
Chart 1 shows employment from the household and payroll surveys from January 1994 through the
most recent month. Two variations of household survey employment used in BLS research are
presented (these variations differ from the official series that appears in the "Employment Situation" and
in the public database available through the BLS website). The green household survey line represents a
version of total household survey employment where the effects of population control revisions in
January 2000 and January of 2003-08 have been smoothed. The red "adjusted" household survey line
represents the smoothed household survey employment series that has been further modified to make it
more similar in concept and definition to payroll survey employment. This adjustment to household
survey employment subtracts from total employment agriculture and related employment,
nonagricultural self employed, unpaid family and private household workers, and workers absent
without pay from their jobs, and then adds nonagricultural wage and salary multiple jobholders.
Chart 1 shows that, because of its broader employment definition, the household survey employment
level (green line) normally exceeds that of the payroll survey. When the household survey is adjusted to
more closely match the payroll survey definition (red line), trend discrepancies between the two surveys
are more discernible. In particular, there is an obvious multi-year period from the late 1990s until the
onset of the 2001 recession when payroll employment was growing significantly faster than household
survey employment.
4
September 5, 2008
Chart 1. Household and payroll survey employment,
seasonally adjusted, 1994-2008
Numbers in thousands
150,000
145,000
140,000
Household
survey
135,000
130,000 Payroll survey
125,000 Adjusted
household
120,000 survey
115,000
110,000
105,000
100,000
1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008
NOTE: The household series presented here has been smoothed for population control revisions. The "adjusted"
household series has been adjusted to an employment concept more similar to the payroll survey's and
smoothed for population control revisions. Shaded area indicates recession.
SOURCE: Bureau of Labor Statistics, September 5, 2008.
5
September 5, 2008
Chart 2 shows the same payroll and household employment series as chart 1, but highlights only the
2001 recession and post-recessionary period from March 2001 through the most recent month. The
Business Cycle Dating Committee of the National Bureau of Economic Research (NBER) designated
March 2001 as the most recent business cycle peak and November 2001 as the most recent trough. (The
NBER is a private, nonprofit, nonpartisan research organization that is the generally acknowledged
arbiter of business cycle dating.)
Chart 2. Household and payroll survey employment,
seasonally adjusted, March 2001-August 2008
Numbers in thousands
150,000
148,000
Household
146,000 survey
144,000
142,000
Adjusted
140,000 household
survey
138,000
136,000 Payroll survey
134,000
132,000
130,000
128,000
126,000
1 1 1 1 2 2 2 2 3 3 3 3 4 4 4 4 5 5 5 5 6 6 6 6 7 7 7 7 8 8 8
- 0 -0 - 0 -0 - 0 -0 - 0 -0 - 0 -0 - 0 -0 - 0 -0 - 0 -0 - 0 -0 - 0 -0 - 0 -0 - 0 -0 - 0 -0 - 0 -0 - 0 -0 - 0
a r J un e p e c a r J un e p e c a r J un e p e c a r J un e p e c a r J un e p e c a r J un e p e c a r J un e p e c a r J un u g
M S D M S D M S D M S D M S D M S D M S D M A
NOTE: The household series presented here has been smoothed for population control revisions. The "adjusted"
household series has been adjusted to an employment concept more similar to the payroll survey's and
smoothed for population control revisions. Shaded area indicates recession.
SOURCE: Bureau of Labor Statistics, September 5, 2008.
6
September 5, 2008
Box 2 shows the change in employment levels from the payroll and household surveys as measured
across the following time periods: 1) over the most recent month, 2) over the most recent year, 3) since
March 2001, the last business cycle peak, and 4) since November 2001, the last business cycle trough.
The peak and trough dates are determined by the National Bureau of Economic Research (NBER).
Box 2. Recent trends in payroll and household survey employment
Numbers in thousands
Over-the-month Over-the-year From From
change: change: March 2001 November 2001
July- August 2007- (peak)- (trough)-
August 2008 August 2008 August 2008 August 2008
Payroll survey:
total nonfarm -84 -283 4,973 6,572
employment,
seasonally adjusted¹
Household survey:
total employment,
smoothed for -342 295 7,678 9,215
population control
revisions and
seasonally adjusted
Difference 258 578 2,705 2,643
¹ Payroll employment for August 2008 is preliminary and subject to revision.
NOTE: The household survey figures in Box 2 are calculated from a variation of household survey
employment used in BLS research (also shown by the green lines in Charts 1 and 2). This version of
household survey employment smoothes out the effects of population control revisions to the survey in
January of 2003-08.
7
September 5, 2008
Box 3 shows employment trends in the payroll and household surveys over the same periods as in Box
2, but this illustration uses adjusted household employment that is more comparable to the payroll
survey (also shown in Charts 1 and 2). Even with this adjustment, the difference in employment change
as measured by the two surveys since March or November of 2001 is significant.
Box 3. Recent trends in payroll employment and household survey employment adjusted to an
employment concept more similar to that of the payroll survey
Numbers in thousands
Over-the-month Over-the-year From From November
change: change: March 2001 2001
July- August 2007- (peak)- (trough)-
August 2008 August 2008 August 2008 August 2008
Payroll survey:
total nonfarm -84 -283 4,973 6,572
employment,
seasonally adjusted¹
Household survey:
total employment,
smoothed for
population control 49 330 8,482 9,794
revisions, adjusted
to be more like the
payroll survey, and
seasonally adjusted
Difference 133 613 3,509 3,222
¹ Payroll employment for August 2008 is preliminary and subject to revision.
NOTE: The household survey figures in Box 3 are calculated from a variation of household
employment used in BLS research (also shown by the red lines in Charts 1 and 2). This version of
household employment adjusts household survey employment to make it more similar in concept and
definition to payroll employment. This adjustment to household survey employment subtracts from total
employment agriculture and related employment, nonagricultural self employed, unpaid family and
private household workers, and workers on unpaid leave from their jobs, and then adds nonagricultural
wage and salary multiple jobholders. It also smoothes out the effects of population control revisions to
the survey in January of 2003-08.
8
September 5, 2008
Possible causes of differences in employment trends
The following summarizes some issues with the surveys that are important when comparing changes in
employment from the two sources.
Sampling error The payroll survey has a much larger sample size than the household survey. The
payroll survey's active sample covers approximately 400,000 business establishments of all sizes
representing about one-third of total nonfarm employment. The household survey is much smaller at
60,000 households, covering a very small fraction of total employed persons. Household survey
employment is therefore subject to larger sampling error, about 4 times that of the payroll survey on a
monthly basis (see Box 1). When looking at short-term trends in either survey, especially over-the-
month changes, it is essential to assess the statistical significance of the change. When comparing the
two series over longer periods of time, however, other factors also need to be considered; some of these
are discussed below.
Payroll survey benchmark The payroll survey estimates are benchmarked once a year against a full
universe count of employment derived from Unemployment Insurance (UI) tax records that nearly all
employers are required to file. The payroll survey's latest benchmark--to March 2007 employment
records--resulted in a downward revision of 293,000 (284,000 on a seasonally adjusted basis), or about
-0.2 percent of total nonfarm employment. The average benchmark revision over the past decade has
been plus or minus 0.2 percent.
With regard to the benchmark source data, BLS has reviewed information from publicly available UI
management reports concerning the timeliness of new business enrollments into the UI system. The
findings are available in the report "Assessing the Timeliness of Business Births in BLS Establishment
Statistics" on the BLS Internet site at http://www.bls.gov/cew/eta581study.pdf.
New business births in the payroll survey The payroll survey sample does not include new firms
immediately. They are incorporated with a lag. In the interim, a model-based estimate is used each
month to account for employment resulting from new firm births. Technical information about the
birth/death model used in the payroll survey estimates is on the BLS Internet site at
http://www.bls.gov/ces/cesbdtech.htm. The latest adjustments resulting from the birth/death model are
available at http://www.bls.gov/web/cesbd.htm.
Job changing - Employment estimates from the payroll survey are a count of jobs, unlike the household
survey which provides a count of employed persons. If a person changes jobs within a payroll survey
reference period, which is defined as the pay period including the 12th of the month, both jobs will be
counted by the payroll survey estimates. If the rate of job-to-job movement changes substantially over
time, it could impact trends produced from the payroll survey. While there is no method to directly
measure effects from job changing, BLS is researching this issue using job change rates from the
household survey. The initial findings of this research are provided in the report "Effects of Job
Changing on Payroll Survey Employment Trends" at http://www.bls.gov/ces/cesjobch.pdf.
9
September 5, 2008
Population controls in the household survey Population controls determine the weights used in the
household survey to adjust the sample results to the overall level of the U.S. population. The population
controls are developed by the U.S. Census Bureau. They are derived from decennial census information
and, between census years, from administrative and other data. There are limitations to the population
control estimates due primarily to the difficulties associated with estimating the net international
migration component. The population controls contributed significantly to the discrepancy between
payroll and household survey employment in the 1980s and 1990s when the household survey showed
less growth than the payroll survey.
Worker classification in the household survey As was illustrated in Box 3 above, adjusting for the
measurable differences in the surveys' employment definitions resolves only a portion of the
discrepancy. This adjustment process is imperfect, however, because precise data are not available in
many cases to make the best possible adjustment. For example, some independent contractors are not
reported as self employed in the household survey, but rather as wage and salary workers. This type of
reporting issue limits BLS' ability to fully reconcile the two employment measures.
"Off-the-books" employment Workers who are paid "off-the-books" are not reported in the payroll
survey. The household survey could possibly include some of these workers, but BLS cannot determine
the extent to which they might be reflected in household survey employment.
Summary
- BLS has estimated the measurable definitional differences between the household and payroll
surveys and found they provide a partial explanation for the employment trend differences. There
are a number of definitional differences between the surveys that cannot be readily measured or
quantified. These differences may contribute to divergences in the surveys' trends, but their effects
are either unknown or can only be conjectured. In addition, although BLS has devoted considerable
attention to this issue, there may be other contributing factors that have not been identified.
- A summary of some of BLS' research was presented to the Federal Economic Statistics Advisory
Committee (FESAC) in October 2003. The paper is available on the BLS Internet site at
http://www.bls.gov/bls/fesacp2101703.pdf. In 2005, a FESAC subcommittee carried out its own
review of the two surveys' employment measures at BLS' request. The FESAC report to BLS is
available on the BLS Internet site at http://www.bls.gov/bls/fesacp2120905.pdf. An article was
published in the February 2006 Monthly Labor Review that discusses BLS research and findings on
the divergence between the two surveys. The article is available on the BLS website at
http://www.bls.gov/opub/mlr/2006/02/art2full.pdf.
- BLS is continuing to investigate possible causes of recent divergences in employment growth
between the payroll and household surveys. BLS also has implemented improvements that
addressed past limitations. The redesign of the payroll survey, for example, led to the use of a
probability sample, more frequent updating of the survey sample frame, and the development of a
more effective means to estimate business births and deaths. With regard to the household survey
population controls, the Census Bureau remains engaged in efforts to improve the intercensal
population estimates. In particular, they have begun utilizing information from the large American
Community Survey (ACS) to improve the estimates of net international migration.
10
September 5, 2008
- Both the payroll and household surveys are needed for a complete picture of the labor market. The
payroll survey provides a highly reliable gauge of monthly change in nonfarm wage and salary
employment. The survey has a large probability sample, and is benchmarked annually to a universe
count of jobs derived from the unemployment insurance tax system. The payroll survey offers
industry and geographic information at very detailed levels. The household survey provides a
broader picture of employment including agriculture and the self employed, as well as detailed
information on the demographic composition of the employed and the unemployed.
Population control adjustments to the household survey
January 2008 adjustment As part of its annual review of intercensal population estimates, the U.S.
Census Bureau determined that a downward adjustment should be made to the household survey
population controls. This adjustment stemmed from revised estimates of net international migration and
the institutional population for 2000 through 2007 and updated information on births and deaths. In
keeping with usual practice, the new controls were used in the survey starting with data for January
2008. Estimates for December 2007 and earlier months were not revised to reflect the new population
controls.
The table below provides a comparison of December 2007 data based on the old and new controls with
the effects on the estimates of the labor force, employment, and unemployment.
January 2008 household survey population control adjustment effect
Employment status of the population, not seasonally adjusted,
December 2007
(Numbers in thousands)
December
2007 as December
published, 2007
without the based on
adjustment to adjusted
population population
controls controls Difference1
Civilian noninstitutional population 233,156 232,411 -745
Civilian labor force 153,705 153,068 -637
Participation rate 65.9 65.9 -.1
Employed 146,334 145,736 -598
Employment-population ratio 62.8 62.7 -.1
Unemployed 7,371 7,331 -40
Unemployment rate 4.8 4.8 .0
Not in labor force 79,451 79,334 -107
1
Differences are calculated from unrounded estimates.
11
September 5, 2008
Previous population control adjustments
In January 2003, BLS introduced two separate adjustments that significantly increased the household
survey population controls and had a major impact on employment levels.
1) Beginning with household survey estimates for January 2000 forward, the population controls
were revised upward to reflect the results of Census 2000. Previous estimates used population
controls based on the 1990 census.
2) In January 2003, the household survey population controls were adjusted upward to reflect
higher estimates of net international migration in the population from 2000 through 2002.
The 2004 adjustment in population controls resulted in a fairly significant level shift in January 2004
employment. The adjustments in 2005-07 had a relatively minor effect on employment.
The following table shows the employment effect of population control adjustments made in January of
2000 and 2003-07.
Effect on household survey employment
from population control adjustments,
2000-07
(In thousands)
January 2000..................... + 1,555
January 2003..................... + 576
January 2004..................... - 409
January 2005...................... - 45
January 2006..................... - 123
January 2007...................... +153
Interpreting household data with the population control adjustments
The adjustments to the population controls introduced each year represent the cumulative over- or
under-estimation of population since the last decennial census. For example, the January 2000
adjustment represented the cumulative underestimation over the 10-year period since the 1990 census,
whereas the January 2007 adjustment represented the cumulative underestimation during the 7-year
period since Census 2000.
The level shifts in household survey employment resulting from these population adjustments make it
difficult for data users to compare changes in employment over time periods that include these
adjustments. As a convenience to its data users, BLS created a research series that smoothes out the
level shifts in employment resulting from the January 2000 and January 2003-08 population control
adjustments over a multi-year period rather than incorporating the entire change in January of the years
that they were implemented.
12
September 5, 2008
This household employment research series was used in Charts 1 and 2 and Box 2 above to provide a
clearer picture for analysis. The full series, 1990-2007, is shown in the table below. Users should be
aware that this research series will not match the official estimates in BLS publications and on the BLS
website.
Household Survey Employment Smoothed for Population Controls, Seasonally Adjusted,
January 1990-December 2007
(In thousands)
January February March April May June July August September October November December
1990 119,093 119,082 119,238 118,898 119,209 119,052 118,891 118,894 118,628 118,651 118,432 118,379
1991 118,089 117,915 117,823 118,293 117,634 117,845 117,785 117,712 118,169 118,052 118,033 117,740
1992 118,265 118,050 118,454 118,748 118,709 118,764 119,071 119,195 119,101 119,020 119,280 119,413
1993 119,503 119,715 119,995 119,938 120,594 120,781 120,970 121,373 121,081 121,363 121,722 122,031
1994 122,547 122,679 122,534 122,908 123,497 123,277 123,362 124,013 124,372 124,811 125,230 125,448
1995 125,402 125,681 125,720 125,722 125,207 125,321 125,629 125,677 125,972 126,241 126,052 125,963
1996 126,013 126,542 126,779 126,924 127,189 127,562 127,922 128,161 128,540 128,909 128,801 128,904
1997 129,358 129,370 129,981 130,247 130,584 130,544 130,970 131,172 131,194 131,368 131,859 131,898
1998 131,958 132,053 132,072 132,484 132,614 132,545 132,643 132,718 133,333 133,359 133,655 133,994
1999 134,436 134,276 134,381 134,402 134,775 134,855 134,905 135,097 135,227 135,529 135,862 136,092
2000 136,560 136,600 136,704 137,274 136,635 136,946 136,538 136,670 136,902 137,098 137,334 137,627
2001 137,792 137,627 137,799 137,316 137,110 136,892 137,091 136,262 136,868 136,415 136,262 136,072
2002 135,726 136,465 136,205 136,155 136,569 136,446 136,445 136,738 137,336 137,043 136,556 136,462
2003 136,864 136,914 136,851 137,034 136,931 137,161 136,831 136,891 136,935 137,294 137,716 137,688
2004 138,141 138,201 138,086 138,332 138,499 138,818 139,201 139,215 139,123 139,372 139,853 139,739
2005 139,864 139,988 140,191 140,864 141,210 141,315 141,655 142,050 142,016 142,193 142,138 142,346
2006 142,771 143,042 143,294 143,462 143,754 144,030 143,951 144,322 144,492 145,036 145,219 145,579
2007 145,387 145,354 145,604 145,167 145,360 145,527 145,479 145,182 145,681 145,432 146,054 145,614
NOTE: This series reflects seasonally adjusted CPS employment that has been revised from January 1990-December 2007 to smooth out the effects
of population control revisions introduced in January 2000 and January of 2003-08.
Source: Bureau of Labor Statistics, February 1, 2008.
13
September 5, 2008
Box 3 used a variation of the smoothed household survey employment research series that was adjusted
to be more similar in concept and definition to payroll employment. That series, which begins in
January 1994, is provided below.
Household Survey Employment Smoothed for Population Controls and Adjusted to a Payroll Concept, Seasonally Adjusted
January 1994-August 2008
(In thousands)
January February March April May June July August September October November December
1994 113,684 113,268 113,797 114,366 114,603 114,661 114,826 115,260 115,800 116,101 116,345 116,565
1995 116,763 117,097 117,018 117,094 117,226 117,443 117,750 117,667 117,720 117,766 117,661 117,817
1996 116,727 118,208 118,582 118,144 118,873 119,334 119,547 120,141 120,435 120,760 121,146 120,716
1997 120,629 121,144 121,532 122,202 122,348 122,804 123,192 123,238 123,276 123,553 123,839 123,888
1998 123,888 124,044 124,253 124,055 124,499 124,470 124,362 124,848 125,252 125,292 125,820 126,380
1999 126,638 126,653 126,721 126,680 126,798 126,833 126,904 127,166 127,296 127,784 128,227 128,331
2000 128,820 128,918 128,930 130,038 129,183 129,347 129,458 129,474 129,557 130,076 130,030 130,427
2001 130,123 130,125 130,100 129,740 129,977 129,717 130,188 129,509 129,632 128,932 128,788 128,833
2002 128,685 129,580 129,276 129,442 129,339 129,440 129,264 130,100 130,239 129,525 128,892 129,356
2003 129,547 129,842 129,673 129,905 129,748 129,755 129,393 129,511 129,226 129,551 129,720 129,752
2004 130,372 130,514 130,868 130,854 131,127 131,404 131,743 131,696 131,894 132,156 132,305 132,517
2005 132,068 132,419 132,665 133,267 133,435 133,902 134,320 134,702 134,775 134,767 134,779 135,072
2006 135,186 135,234 135,474 135,502 136,116 136,122 136,419 136,783 137,088 137,479 137,729 137,803
2007 137,866 137,548 137,972 137,853 137,959 138,101 138,117 138,252 138,485 138,448 139,053 138,114
2008 138,653 138,527 138,680 139,254 138,637 138,888 138,533 138,582
NOTE: This series represents not seasonally adjusted household survey employment that has been adjusted to an employment concept more similar
to the payroll survey by subtracting from total employment agriculture and related employment, the self employed, unpaid family and private household
workers, and workers on unpaid absences and then adding nonagricultural wage and salary multiple jobholders. The data were then revised to smooth out
the effects of population control revisions introduced in January 2000 and January of 2003-08. The resulting employment series was then seasonally
adjusted.
Source: Bureau of Labor Statistics, September 5, 2008.
14
September 5, 2008
Benchmark revisions to the payroll survey
Benchmark revisions are a standard part of the payroll survey estimation process. The benchmark
adjustment represents a once-a-year re-anchoring of sample-based employment estimates to full
employment counts available through unemployment insurance (UI) tax records filed by nearly all
employers with State Employment Security Agencies.
The incorporation of March 2007 benchmarks published on February 1, 2008, led to a revision of data
for the period subsequent to the last benchmark; that is, for April 2006 forward. Also with this release,
payroll survey data were updated to the 2007 North American Industry Classification System (NAICS)
from the 2002 NAICS. Data from January 1990 forward were subject to revision resulting from the
NAICS classification change; the seasonally adjusted series from January 1990 forward also were
subject to revision due to the introduction of updated seasonal adjustment factors.
March 2007 Benchmark Effects on the Nonfarm Payroll Series
The total nonfarm employment level for March 2007 was revised downward by 293,000 (284,000 on a
seasonally adjusted basis) or -0.2 percent. The average benchmark revision over the past decade has
been plus or minus 0.2 percent.
Following standard BLS methodology, estimates were recalculated for the year preceding and the
months following the March 2007 benchmark reference month. The March 2007 UI-based benchmark
level replaced the March 2007 sample-based employment estimate. The difference between the
benchmark level and the estimate was wedged back to the previous benchmark level: 1/12 of the
difference was added to the April 2006 employment level, 2/12 to May 2006 and so forth, through
February 2007, which received 11/12 of the difference.
Estimates for April 2007 forward were recalculated by applying over-the-month changes from the
sample to the new benchmark level, along with recomputed net birth/death factors, and new seasonal
adjustment factors.
15
September 5, 2008
The net impact of the benchmarking process for January through October 2007 is shown in the table
below.
Revisions in total nonfarm employment, seasonally adjusted, in thousands
Employment Over-the-month Over-the-
levels as Employment changes as month
previously levels as previously changes as Difference
published revised published revised
2007
January 137,329 137,108 162 126 -36
February 137,419 137,133 90 25 -65
March 137,594 137,310 175 177 2
April 137,716 137,356 122 46 -76
May 137,904 137,518 188 162 -26
June 137,973 137,625 69 107 38
July 138,066 137,682 93 57 -36
August 138,159 137,756 93 74 -19
September 138,203 137,837 44 81 37
October 138,362 137,977 159 140 -19
http://www.bls.gov/web/ces_cps_trends.pdf
16