U.S. Department of Labor Elaine L. Chao, Secretary
U.S. Bureau of Labor Statistics
Philip L. Rones, Deputy Commissioner
September 2007
Bulletin 2590
Contents
Overview
Occupational Earnings Tables: United States, December 2005 – January 2007
(average reference date June 2006)
Relative Standard Error (RSE) tables to accompany mean hourly,
weekly, and annual earnings tables
Appendix A: Technical Note
Appendix B: Occupational Descriptions (PDF)
Appendix C: Survey Areas and Geographic Coverage (PDF)
Chartbook
Overview
The National Compensation Survey (NCS) provides comprehensive measures of
occupational earnings, compensation cost trends, benefit incidence, and
detailed benefit provisions. This bulletin presents estimates of occupational
pay for the Nation. These national estimates originate from the NCS locality survey
data and are weighted to represent the Nation as a whole. Data for more than
one-half of the 152 individual NCS localities used for national estimates have been
previously published. This includes pay estimates for workers in major
sectors within the United States economy in 2006: Civilian, private
industry, and State and local government; and by various occupational and
establishment characteristics. The civilian economy, by NCS definition,
excludes Federal Government, agricultural, and household workers.
Questions regarding these data and recent and
historical NCS wage data can be addressed by calling the information line at
(202) 691-6199 or by e-mail to
NCSInfo@bls.gov. This information is available to sensory-impaired individuals on request. Voice
phone: (202) 691-5200; Federal Relay Service: 1 (800) 877-8339.
Data requests also may be sent by mail to the U.S. Bureau of Labor Statistics,
Division of Compensation Data Analysis and Planning, 2 Massachusetts Avenue, NE, Room 4175,
Washington, DC 20212. Material in this publication is in the public
domain and, with appropriate credit, may be reproduced without permission.
U. S. Bureau of Labor Statistics (BLS)
field economists collected and reviewed the survey data. The Office of Compensation and
Working Conditions, in cooperation with the Office of Field Operations and the
Office of Technology and Survey Processing in the BLS National Office, designed
the survey, processed the data, and prepared the survey for publication. The survey could not have been conducted
without the cooperation of the many private businesses and government
jurisdictions that provided pay data included in this bulletin. BLS thanks these respondents for their cooperation.
This edition of the National Compensation Survey (NCS) annual bulletin on occupational wages in the
United States has undergone several major changes since its last publication. The most noticeable change is the bulletin's format.
Formerly, the NCS annual wage bulletin was printed in soft-cover book format, with nearly 150 pages of data tables, as well as
posted on the Bureau of Labor Statistics Web site in TXT and PDF formats. Starting with the 2006 national wage bulletin,
the overview, explanatory text, data tables, and technical note are published exclusively in digital formats — on CD and
on BLS Internet pages. The chartbook that holds the CD includes highlights of the data in the annual bulletin,
depicted in a variety of charts and graphs.
This edition includes changes in data content, as well. Major changes are listed here and described
below:
- The 2000 Standard Occupational Classification (SOC) system
- The 2002 North American Industry Classification System (NAICS)
- Imputation for temporary nonresponse situations
- Benchmarking of estimated employment
- New tables and detail
New occupational and industry classification of
workers. Since its inception in 1996, NCS wage surveys have published data on occupations according to the 1990
Occupational Classification System (OCS). Beginning with locality bulletins published in September 2006, new NCS
wage publications, including the 2006 national wage bulletin, classify occupations
according to the 2000 Standard Occupational Classification (SOC) codes. The
2000 SOC system defines more than 800 detailed occupations and is designed to
reflect the current occupational structure in the United States better than previous
occupational systems. Detailed occupations are combined into broad occupations,
broad occupations are combined into minor groups, and minor groups are combined
into major groups. For details on the SOC occupational titles used for the NCS
wage bulletins, see appendix B. The design of several levels of aggregation is intended to meet the widely varying
needs of data users. For more information on the SOC classification system, see: www.bls.gov/soc/.
Also beginning with the locality bulletins published in September 2006, new NCS wage publications,
including the 2006 national bulletin, classify the type of establishment in
which employees work according to the 2002 North American Industry
Classification System (NAICS). The NCS had formerly published its wage data
according to the 1987 Standard Industrial Classification system (SIC) since the
survey began in 1996. For more detail on
the NAICS classification system, see: www.bls.gov/bls/naics.htm.
These occupational and industry classification changes are part of a major initiative to convert all Federal
surveys to the NAICS and SOC classification systems. For more information on this transition, see
www.bls.gov/soc/socimp.htm.
Imputation for temporary nonresponse of
establishments. For the first time, the NCS wage program is imputing data for temporary nonresponse
situations. The National Compensation Survey is voluntary, and a company
official may refuse to participate in the initial survey or may be unwilling or
unable to update previously collected data during a subsequent contact. For
those situations where previous wage data cannot be updated, an estimate for
the missing data is imputed using information obtained from similar
establishments and occupations.
Benchmarking of estimated employment. Post stratification,
also known as benchmarking, has been introduced to adjust survey sample weights
so that these weights reflect the current count of employment by industry.
Initial weights are derived when the sample of establishments are selected,
reflecting employment distribution by industry at that time. Those weights may
be up to 7 years old for the oldest panel of five sample rotation panels at the
time of publication. Benchmarking adjusts those weights to reflect the
employment distribution by industry for the reference date of the data.
New tables and detail. The 2006 NCS national bulletin has
added many new tables: wages for supervisory occupations, private industry
sector, nonprofit establishments, and hospitals; wages by percentile; and other
new details. For a full description of
these changes, see "Change Comes to the National Compensation Survey
Locality Wage Bulletins, Compensation and Working Conditions Online, available on the Internet, at:
www.bls.gov/opub/cwc/cm20070122ar01p1.htm.
The tables are listed below.
(Back to top)
Occupational Earnings Tables: United States, December 2005 –
January 2007 (average reference date June 2006)
The 2006 NCS national wage bulletin includes occupational earnings tables 1-41;
relative standard errors of the estimates for tables 2-7, 12, 24-26, 30-34, and
40-41; and appendix tables 1 and 2. The relative standard errors tables are in the section below the occupational earnings
tables; they are titled and numbered to correspond to their respective
wage-estimates tables. Appendix tables 1 and 2 are part of appendix A.
Summary table. Table 1 presents an overview of all tables in
this bulletin. Mean hourly earnings, weekly hours, and relative standard errors are given for Civilian, private
industry, and State and local government workers by selected worker and
establishment characteristics. Worker characteristics include high-level and intermediate occupational aggregation,
full-time and part-time status, union and nonunion status, and time and incentive
pay status. Establishment characteristics
include goods producing, service providing, and size of establishment.
- Table 1. Summary: Mean hourly earnings and weekly hours for selected worker and
establishment characteristics. (TXT) (PDF 21K)
Full-time and part-time workers. Mean and median
hourly, weekly, and annual earnings estimates are provided for full-time
workers in each of the three major sectors, as well as mean weekly and annual
hours worked. Further tables provide mean hourly earnings estimates for full-time and part-time workers by level within
occupation.
- Table 2. Full-time and part-time workers: Mean hourly earnings for major
occupational groups. (TXT) (PDF 16K)
- Table 3. Civilian full-time workers: Mean and median hourly, weekly, and annual earnings and mean weekly and annual hours.
(TXT) (PDF
118K)
- Table 4. Full-time private industry workers: Mean and median hourly, weekly, and
annual earnings and mean weekly and annual hours. (TXT) (PDF 111K)
- Table 5. Full-time State and local government workers: Mean and median hourly,
weekly, and annual earnings and mean weekly and annual hours. (TXT) (PDF 71K)
- Table 6. Full-time State government workers: Mean and median hourly, weekly, and
annual earnings and mean weekly and annual hours. (TXT) (PDF 46K)
- Table 7. Full-time local government workers: Mean and median hourly, weekly, and
annual earnings and mean weekly and annual hours. (TXT) (PDF 63K)
Work levels. Levels are standardized measures of duties and
responsibilities that apply to all occupations.
The NCS National bulletin has previously published levels data, but this
is the first time combined levels have been published for the Nation. Table 11 shows four bands I through IV, which
combine levels 1 through 4; levels 5 through 8; levels 9 through 12; and levels
13 through 15; respectively. The publication of combined levels is intended to
make the wage estimates more useful to compensation analysts.
- Table 8. Civilian workers: Mean hourly earnings for full-time and
part-time workers by work levels. (TXT) (PDF 302K)
- Table 9. Private industry workers: Mean hourly earnings for full-time and
part-time workers by work levels. (TXT) (PDF 272K)
- Table 10. State and local government workers: Mean
hourly earnings for full-time and part-time workers by work levels. (TXT) (PDF 140K)
- Table 11. Combined work levels for civilian workers: Mean hourly earnings for full-time and part-time workers.
(TXT) (PDF 180K)
Union and nonunion workers. Separate estimates on mean
hourly occupational earnings are provided for union and nonunion workers for
each of the three major sectors of the economy and for a detailed occupational
groups as well as for detailed occupations.
- Table 12. Union and nonunion workers: Mean hourly earnings by major sector and
for major occupational groups. (TXT) (PDF 15K)
- Table 13. Union and nonunion workers: Mean hourly earnings for civilian
workers by bargaining status. (TXT) (PDF 94K)
Time and incentive workers. This table provides hourly
earnings estimates for workers paid on a time or incentive basis for those who
work in the Civilian and private industry sectors.
- Table 14. Workers paid on time and incentive basis:
Mean hourly earnings for civilian and private industry workers in major occupational groups.
(TXT) (PDF 18K)
Percentiles. The 2006 National bulletin provides estimates on the mean hourly wage for the 10th
percentile, the 25th percentile, 50th percentile (the
median), the 75th percentile, and the 90th percentile of
occupational wages separately for all Civilian, full-time Civilian, part-time Civilian,
all private industry, full-time private industry, part-time private industry, all
State and local government, full-time State and local government, and part-time
State and local government workers.
- Table 15. Civilian workers: Hourly wage percentiles.
(TXT) (PDF 78K)
- Table 16. Full-time Civilian workers: Hourly wage percentiles. (TXT)
(PDF 76K)
- Table 17. Part-time Civilian workers: Hourly wage percentiles.
(TXT) (PDF 43K)
- Table 18. Private industry workers: Hourly wage percentiles.
(TXT) (PDF 72K)
- Table 19. Full-time private industry workers: Hourly wage percentiles.
(TXT) (PDF 70K)
- Table 20. Part-time private industry workers: Hourly wage percentiles.
(TXT) (PDF 37K)
- Table 21. State and local government workers: Hourly wage percentiles.
(TXT) (PDF 47K)
- Table 22. Full-time State and local government workers: Hourly wage percentiles.
(TXT) (PDF 46K)
- Table 23. Part-time State and local government workers: Hourly wage percentiles.
(TXT) (PDF 27K)
Supervisory occupations. The set of tables on
supervisory occupations are new to the national bulletin this year:
Mean and median weekly and annual occupational earnings and mean weekly and annual hours for workers in
management occupations by supervisory responsibility: team leaders, first-line,
second-line, and third-line supervisory duties — provided separately for the Civilian,
private industry, and State and local governments sectors.
- Table 24. Civilian supervisory workers: Mean and median weekly and annual
earnings and mean weekly and annual hours.
(TXT) (PDF 20K)
- Table 25. Private industry supervisory workers: Mean and median weekly and annual
earnings and mean weekly and annual hours.
(TXT) (PDF 20K)
- Table 26. State and local government supervisory workers: Mean and median weekly and
annual earnings and mean weekly and annual hours.
(TXT) (PDF 17K)
Size of establishment. Estimates for mean hourly earnings for workers in major occupational groups by size of
establishment — 1-49 workers, 50-99 workers, 100-499 workers, and 500 workers
or more—are given separately for the Civilian, private industry, and State and
local government sectors. There are also
separate tables for detailed occupational estimates on mean and median hourly,
weekly, and annual earnings and mean weekly and annual hours of full-time
private industry workers in establishments with fewer than 100 workers and
those in establishments with 100 workers or more.
- Table 27. Size of establishment: Mean hourly earnings
of workers in Civilian establishments for major occupational groups.
(TXT) (PDF 15K)
- Table 28. Size of establishment: Mean hourly earnings
of workers in private industry establishments for major occupational groups.
(TXT) (PDF 15K)
- Table 29. Size of establishment: Mean hourly earnings
of workers in State and local government establishments for major
occupational groups. (TXT) (PDF 15K)
- Table 30. Private industry establishments with fewer
than 100 workers: Mean and median hourly, weekly, and annual earnings and
mean weekly and annual hours for full-time workers.
(TXT) (PDF 88K)
- Table 31. Private industry establishments with 100
workers or more: Mean and median hourly, weekly, and annual earnings and
mean weekly and annual hours for full-time workers.
(TXT) (PDF 102K)
Private industry sector. The 2006 national wage
bulletin includes a new table on mean hourly earnings for workers by sector of
private industry, for major occupational groups.
- Table 32. Private industry sector: Mean hourly earnings for major occupational groups (TXT) (PDF 13K)
Nonprofit establishments. For the first time in the NCS national wage bulletin,
mean and median hourly, weekly, and annual earnings and mean weekly and annual hours for private industry full-time
workers who work in nonprofit establishments have been published by detailed
occupation and level.
- Table 33. Nonprofit establishments: Mean and median hourly, weekly, and annual earnings and mean weekly and annual hours of
full-time workers in private industry, by work levels.
(TXT) (PDF 123K)
Hospitals. The bulletin provides a new table on mean
and median hourly, weekly, and annual earnings and mean weekly and annual hours
for full-time Civilian workers in hospitals, by detailed occupation and level.
The bulletin also provides tables for private industry and State and local government sectors on mean hourly earnings
estimates for all, full-time, and part-time workers in hospitals by detailed
occupation.
- Table 34. Civilian full-time workers in hospitals:
Mean and median hourly, weekly, and annual earnings and mean weekly and
annual hours by work levels.
(TXT) (PDF 77K)
- Table 35. Private industry workers in hospitals: Mean
hourly earnings for full-time and part-time workers.
(TXT) (PDF 29K)
- Table 36. State and local government workers in
hospitals: Mean hourly earnings for full-time and part-time workers.
(TXT) (PDF 24K)
Metropolitan and nonmetropolitan areas. The 2006 NCS national
wage bulletin includes estimates of mean hourly earnings for Civilian, State
and local government, and private industry workers by metropolitan,
nonmetropolitan, and geographic areas; estimates of mean hourly earnings for Civilian
workers in metropolitan and nonmetropolitan areas by worker and establishment
characteristics; and estimates of mean hourly wages for Civilian workers in
metropolitan and nonmetropolitan areas by geographic area.
The geographic areas in these tables are Census divisions. See appendix C for more
information. Detailed tables of occupational wages by Census region and division, which were published in previous NCS national
bulletins, are not included here; however, they will be included in the 2006 NCS
Census division wage bulletins, which are forthcoming.
-
Table 37. Summary: Mean hourly earnings and weekly hours for metropolitan, nonmetropolitan,
and geographic areas. (TXT) (PDF 13K)
- Table 38. Summary: Mean hourly earnings and weekly hours of civilian workers in metropolitan
and nonmetropolitan areas by worker and establishment characteristics.
(TXT) (PDF 16K)
- Table 39. Summary: Mean hourly earnings and weekly hours for metropolitan and nonmetropolitan
areas by geographic area. (TXT) (PDF 13K)
- Table 40. Civilian workers in metropolitan areas: Mean and median hourly, weekly, and annual
earnings and mean weekly and annual hours. (TXT) (PDF 114K)
- Table 41. Civilian workers in nonmetropolitan areas:
Mean and median hourly, weekly, and annual earnings and mean weekly and
annual hours. (TXT) (PDF 73K)
Combined Wage Tables. Wages tables 1-15, 16-30, 31-41, and all wage tables are given here for ease of printing many tables at once.
- Wage Tables 1-15 (PDF 1360K)
- Wage Tables 16-30 (PDF 483K)
- Wage Tables 31-41 (PDF 510K)
- All Wage Tables (TXT) (PDF 3MB)
(Back to top)
Relative Standard Error (RSE) tables to accompany mean hourly, weekly, and annual earnings tables:
- RSE Table 2. Full-time and part-time workers: Relative standard errors of mean hourly
earnings for major occupational groups. (TXT) (PDF 17K)
- RSE Table 3. Civilian full-time workers: Relative standard errors of mean hourly,
weekly, and annual earnings. (TXT) (PDF 89K)
- RSE Table 4. Full-time private industry workers: Relative standard errors of mean hourly,
weekly, and annual earnings. (TXT) (PDF 84K)
- RSE Table 5. Full-time State and local government workers: Relative standard errors
of mean hourly, weekly, and annual earnings. (TXT) (PDF 55K)
- RSE Table 6. Full-time State government workers: Relative standard errors of mean hourly,
weekly, and annual earnings. (TXT)
(PDF 41K)
- RSE Table 7. Full-time local government workers: Relative standard errors of mean hourly,
weekly, and annual earnings. (TXT) (PDF 47K)
- RSE Table 12. Union and nonunion workers: Relative standard errors of mean hourly
earnings by major sector and for major occupational groups. (TXT) (PDF 14K)
- RSE Table 24. Civilian supervisory workers: Relative standard errors of mean weekly
and annual earnings for selected management occupations.
(TXT) (PDF 16K)
- RSE Table 25. Private industry supervisory workers: Relative standard errors of mean weekly
and annual earnings for selected management occupations.
(TXT) (PDF 23K)
- RSE Table 26. State and local government supervisory workers: Relative standard errors
of mean weekly and annual earnings for selected management occupations.
(TXT) (PDF 21K)
- RSE Table 30. Private industry establishments with fewer than 100 workers: Relative standard errors of mean hourly, weekly,
and annual earnings for full-time workers.
(TXT ) (PDF 68K)
- RSE Table 31. Private industry establishments with 100 workers or more: Relative standard errors of mean hourly, weekly, and
annual earnings for full-time workers.
(TXT) (PDF 79K)
- RSE Table 32. Private industry sector: Relative standard
errors of mean hourly earnings for major occupational groups.
(TXT) (PDF 13K)
- RSE Table 33. Nonprofit establishments: Relative
standard errors of mean hourly, weekly, and annual earnings of full-time
workers in private industry, by work levels.
(TXT ) (PDF 97K)
- RSE Table 34. Civilian full-time workers in hospitals: Relative standard errors of mean hourly, weekly, and annual
earnings by work levels. (TXT) (PDF 61K)
- RSE Table 40. Civilian workers in metropolitan areas: Relative standard errors of mean
hourly, weekly, and annual earnings.
(TXT) (PDF 86K)
- RSE Table 41. Civilian workers in nonmetropolitan areas: Relative standard errors of mean hourly, weekly, and annual
earnings. (TXT) (PDF 56K)
Combined RSE Tables. All of the RSE tables are given here for ease of printing many tables at once.
- All RSE Tables (PDF 710K)
Appendix A: Technical Note
Appendix table 1. Number of workers represented by
the survey. (TXT) (PDF 10K)
Appendix table 2. Survey establishment response.
(TXT) (PDF 10K)
This section provides basic information on the procedures and concepts.
It is divided into three parts: Planning for the survey; data
collection; and processing and analyzing the data. Although this section
answers some questions commonly asked by data users, it is not a comprehensive
description of all of the steps required to produce the data.
Planning for the survey
The overall design of the National Compensation Survey (NCS) includes questions of
survey scope, sampling frame, and sample selection.
Survey scope
This survey covered establishments employing one worker or more in private
goods-producing industries (mining, construction, and manufacturing); private
service-providing industries (trade, transportation, and utilities,
information, financial activities, professional and business services,
education and health services, leisure and hospitality, and other services);
State governments; and local governments employing 50 or more workers.
Agriculture, forestry, fishing and hunting, private households, and the Federal
Government were excluded from the scope of the survey. For purposes of this
survey, an establishment is an economic unit that produces goods or services, a
central administrative office, or an auxiliary unit providing support services
to a company. For private industries in this survey, the establishment is
usually at a single physical location. For State and local governments, an
establishment is defined as all locations of a government agency within the
sampled area.
Sampling frame
The list of establishments from which the survey sample was selected (sampling
frame) was developed from State unemployment insurance reports. Due to the
volatility of industries within the private sector, sampling frames were
developed using the most recent month of reference available at the time the
sample was selected. Approximately one-fifth of the sample is reselected each
year.
Sample design
The sample for this survey area was selected using a two-stage stratified design
with probability proportional to employment sampling at each stage. The first
stage of sample selection was a probability sample of establishments. The
sample of establishments was drawn by first stratifying the sampling frame by
industry and ownership. The number of sample establishments allocated to each
stratum is approximately proportional to the stratum employment. Each sampled
establishment is selected within a stratum with a probability proportional to
its employment. Use of this technique means that the larger an establishment’s
employment, the greater its chance of selection. Weights were applied to each
establishment when the data were tabulated so that it represents similar units
(by industry and employment size) in the economy that were not selected for
collection. The second stage of sample selection, detailed below, was a
probability sample of occupations within a sampled establishment.
Data collection
The collection of data from survey respondents required detailed procedures. Field
economists collected the data, working out of the U.S. Bureau of Labor
Statistics (BLS) regional offices and visiting each establishment surveyed. Other
contact methods, such as mail and telephone, were used to clarify and update
data.
Occupational selection and classification
Identification of the occupations for which wage data were to be collected was a multi-step
process:
Probability-proportional-to-size selection of establishment jobs
Classification of jobs into occupations based on the 2000 Standard Occupational
Classification (SOC) system
Characterization of jobs as full-time or part-time, union or nonunion, and time or
incentive
Determination of the level of work of each job
For each occupation, wage data were collected for those workers whose jobs could be
characterized by the criteria identified in the last three steps. If a specific
work level could not be determined, wages were still collected. In step one,
the jobs to be sampled were selected at each establishment by the BLS field
economist. A complete list of employees was used for sampling, with each
selected worker representing a job within the establishment. As with the
selection of establishments, the selection of a job was based on probability proportional
to its size in the establishment. The greater the number of people working in a
job in the establishment, the greater is its chance of selection. The number of
jobs for which data were collected in each establishment was based on the
establishment’s employment size. The number of jobs selected followed this
schedule:
|
Number
of employees
|
Number
of selected jobs
|
|
1–49
|
Up to 4
|
|
50–249
|
6
|
|
250 or more
|
8
|
The second step of the process entailed classifying the selected jobs into
occupations based on their duties. NCS uses the 2000 Standard Occupational
Classification (SOC) system. A selected job may fall into any one of about 800
occupational classifications, from accountant to zoologist. When workers could
be classified in more than one occupation, they were classified in the
occupation that required the higher skill level. When there was no perceptible
difference in skill level, the workers were classified in the occupation that
described their primary activity. Each occupational classification is an
element of a broader classification known as a major group. Occupations can
fall into any of 22 major groups. Appendix B contains a complete list of all
individual occupations, classified by the major group to which they belong.
In step three, certain other job characteristics of the chosen worker were
identified. First, the worker was identified as holding either a full-time or part-time job, based on the
establishment’s definition of those terms. Then, the worker was classified as
having a time versus incentive job, depending on whether any part of pay was
directly based on the actual production of the worker, rather than solely on
hours worked. Finally, the worker was identified as being in a union job or a
nonunion job. For more detail, see the “Definition of terms” section, which
follows.
Occupational leveling
In the last step before wage data were collected, the work level of each selected
job was determined using a point factor leveling process. Point factor leveling matches certain aspects of a job to
specific levels of work with assigned point values. Points for each factor are
then totaled to determine the overall work level for the job. The NCS program
is in the process of converting from a nine-factor to a four-factor
occupational leveling system. The conversion is being phased in via annual NCS
sample replenishment groups and will require several years for full
implementation. The four occupational leveling factors are:
- Knowledge
- Job controls and complexity
- Contacts (nature and purpose)
- Physical environment
Each factor consists of several levels, and each level has an associated description
and assigned points. A knowledge guide for 24 families of closely related
occupations contains short definitions of the point levels of knowledge
expected for the occupations and presents relevant examples. The other three
factors use identical descriptions for all occupational categories and contain
a definition of each point level within each factor. The description within
each factor best matching the job is chosen. The point levels within each
factor are designed to describe the thresholds of distinct levels of work. When
a job does not meet the full description of a point level, the next lowest
point level is used. Points for the four factors are totaled to determine the
overall work level. NCS publishes data for up to 15 work levels. Most
supervisory occupations are evaluated based on their duties and
responsibilities. A modified approach is used for professional and
administrative supervisors when they direct professional work and are paid
primarily to supervise. Such supervisory occupations are leveled based on the
work level of the highest position reporting to them. For a complete
description of point factor leveling, refer to the publication “National
Compensation Survey: Guide for Evaluating Your Firm’s Jobs and Pay,” available
on the Internet, at www.bls.gov/ncs/ocs/sp/ncbr0004.pdf.
Combined work levels
This bulletin includes a table which simplifies the presentation of work levels by
combining them into four broad groups. The groups were determined by
combinations of knowledge, job controls and complexity, contacts, physical
environment, and supervisory duties, and are meant to be comparable across
different occupations. The broad groups and the combined work levels are:
|
Groupdesignation
|
Levelscombined
|
|
Group I
|
Levels 1–4
|
|
Group II
|
Levels 5–8
|
|
Group III
|
Levels 9–12
|
|
Group IV
|
Levels 13–15
|
Collection period
Survey data were collected over a 13-month period for 60 metropolitan areas in the NCS
program. For 20 small metropolitan areas
and all 72 nonmetropolitan areas, data were collected over a 4-month period.
For each establishment in the survey, the data
reflect the establishment’s most recent information at the time of collection.
The data for the National bulletin were
compiled from locality data collected between
December 2005 and January 2007. The
average reference period was June 2006.
Earnings
Earnings were defined as regular payments from the employer to the employee as compensation
for straight-time hourly work, or for any salaried work performed. The
following components were included as part of earnings:
- Incentive pay, including commissions, production bonuses, and piece rates
- Cost-of-living allowances
- Hazard pay
- Payments of income deferred due to participation in a salary reduction plan
- Deadhead pay, defined as pay given to transportation workers returning in a vehicle
without freight or passengers
The following forms of payments were not considered part of straight-time earnings:
- Shift differentials, defined as extra payment for working a schedule that varies
from the norm, such as night or weekend work
- Premium pay for overtime, holidays, and weekends
- Bonuses not directly tied to production (such as Christmas and profit-sharing
bonuses)
- Uniform and tool allowances
- Free or subsidized room and board
- Payments made by third parties (for example, tips)
- On-call pay
To calculate earnings for various periods (hourly, weekly, and annual), data on
work schedules also were collected. For hourly workers, scheduled hours worked
per day and per week, exclusive of overtime, were recorded. Annual weeks worked
were determined. Because salaried workers who are exempt from overtime
provisions often work beyond the assigned work schedule, their typical number
of hours actually worked was collected.
Definition of terms
Full-time worker. Any employee whom the employer considers to be full time.
Part-time worker. Any employee whom the employer considers to be part time.
Time-based worker. Any employee whose earnings are solely tied to an hourly rate or
salary.
Incentive worker. Any employee whose earnings are tied, at least in part, to
commissions, piece rates, production bonuses, or other incentives based on
production or sales.
Nonunion worker. An employee in an occupation not meeting the conditions for union
coverage.
Union worker. Any employee is in a union occupation when all of the following
conditions are met:
- A labor organization is recognized as the bargaining agent for all workers in the occupation
- Wage and salary rates are determined through collective bargaining or negotiations
- Settlement terms, which must include earnings provisions and may include benefit provisions, are
embodied in a signed, mutually binding collective bargaining agreement
Level. A ranking within an occupation based on the requirements of the position.
Processing and analyzing the data
Data were processed and analyzed at the BLS national office following
collection. This includes weighting, adjusting for nonresponse, imputation, benchmarking, and calculating wage
estimates, variances, and other summary statistics.
Weighting and nonresponse
Sample weights were calculated for each establishment and occupation in the survey.
These weights reflected the relative size of the occupation within the
establishment and of the establishment within the sample universe. Weights were
used to aggregate data for the individual establishments or occupations into
the various data series. Some of the establishments surveyed could not supply
or refused to supply information. If data were not provided by a sample member
during the initial interview, the weights of responding sample members in the
same or similar cells were adjusted
to account for the missing data. This technique assumes that the mean value of
data for the nonrespondents equals the mean value of data for the respondents
at some detailed cell level. Responding and nonresponding establishments were
classified into these cells according to industry and employment size.
Responding and nonresponding occupations within responding establishments were
classified into cells that were additionally defined by major occupation group.
If average hourly earnings data were not provided by a sample member during the
update interview, then missing average hourly earnings were imputed by
multiplying prior average hourly earnings by the rate of change in the average
hourly earnings of respondents. The regression model that takes into account
available establishment characteristics is used to derive the rate of change in
the average hourly earnings. Establishments that were determined to be out of
business or outside the scope of the survey had their weights changed to zero.
Estimation
The wage series in the tables are computed by combining the wages for each sampled
occupation. Before being combined, individual wage rates are weighted by the
number of workers; the sample weight, adjusted for nonresponding establishments
and other factors; and the occupation’s scheduled hours of work. The sample
weight reflects the inverse of each unit’s probability of selection at each
sample selection stage and four weight adjustment factors. The first factor
adjusts for establishment nonresponse and the second factor adjusts for
occupational nonresponse. The third factor adjusts for any special situations
that may have occurred during data collection. The fourth factor,
post-stratification, also called benchmarking, is introduced to adjust
estimated employment totals to the current counts of employment by industry.
The latest available employment counts were used to derive average hourly
earnings in this publication. Not all calculated series met the criteria for
publication. Before any series was published, it was reviewed to make sure that
the number of observations underlying it was sufficient. This review prevented
the publication of a series that could have revealed information about a
specific establishment. Estimates of the number of workers represent the total
in all establishments within the scope of the study, and not the number
actually surveyed. Because occupational structures among establishments differ,
estimates of the number of workers obtained from the sample of establishments
serve to indicate only the relative importance of the occupational groups
studied.
Percentiles
The percentiles presented in tables 15 through 23 are computed using earnings
reported for individual workers in sampled establishment jobs and their
scheduled hours of work. Establishments in the survey may report only individual-worker
earnings for each sampled job. For the calculation of percentile estimates, the
individual-worker hourly earnings are appropriately weighted and then arrayed
from lowest to highest. The published 10th, 25th, 50th, 75th, and 90th
percentiles designate position in the earnings distribution within each
published occupation. At the 50th percentile, the median, half of the hours are
paid the same as or more than the rate shown, and half are paid the same as or
less than the rate shown. At the 25th percentile, one-fourth of the hours are
paid the same as or less than the rate shown, while at the 75th percentile,
one-fourth of the hours are paid the same as or more than the rate shown. At
the 10th percentile, one-tenth of the hours are paid the same as or less than
the rate shown, while at the 90th percentile, one-tenth are paid the same as or
more than the rate shown.
Data reliability
The data in this bulletin are estimates from a scientifically selected probability
sample. There are two types of errors possible in an estimate based on a sample
survey, sampling and nonsampling.
Sampling errors occur because observations come only from a sample and not from an
entire population. The sample used for this survey is one of a number of
possible samples of the same size that could have been selected using the
sample design. Estimates derived from the different samples would differ from
one another. A measure of the variation
among these differing estimates is called the standard error or sampling error.
It indicates the precision with which an estimate from a particular sample
approximates the average result of all possible samples. The relative standard
error (RSE) is the standard error divided by the estimate. RSE data are
provided alongside the earnings data in many of the bulletin tables. The
standard error can be used to calculate a confidence
interval around a sample estimate. As an example, table 1 shows mean hourly
earnings for all workers of $19.29 per hour and a relative standard error of
1.2 percent for this estimate. At the 90-percent level, the confidence interval
for this estimate is from $18.91 to $19.67 ($19.29 x 1.645 x 0.012 = $0.3808,
rounded to $0.38); ($19.29 - 0.38 = $18.91; $19.29 + 0.38 = $19.67). If all
possible samples were selected to estimate the population value, the interval
from each sample would include the true population value approximately 90
percent of the time.
Nonsampling errors also affect survey results. They can stem from many sources, such as
inability to obtain information for some establishments, difficulties with
survey definitions, inability of the respondents to provide correct
information, or mistakes in recording or coding the data obtained. Although
they were not specifically measured, the nonsampling errors were expected to be
minimal due to the extensive training of the field economists who gathered the
survey data, computer edits of the data, and detailed data review.
