Technical Note


Overview

   The Occupational Employment and Wages in Green Goods and Services
(GGS-OCC) program provides occupational employment and wage
information for businesses that produce green goods or provide green
services. The GGS-OCC data are based on a sample of approximately
93,000 business establishments classified in 333 industries in which
establishments potentially produce green goods or provide green
services as their primary activity.

   The GGS-OCC estimates are produced by linking data from two
different surveys at the establishment level: the percent of the
establishment's revenue received from green goods and services, from
the Green Goods and Services (GGS) survey; and occupational employment
and wage information, from the Occupational Employment Statistics
(OES) survey. These data are used to produce occupational employment
and wage estimates for three groups of establishments: those that
receive none of their revenue from green goods and services, those
that receive all of their revenue from green goods and services, and
those with revenue from a mix of green and nongreen goods and
services. This release covers only those establishments that receive
100 percent of their revenue from green goods and services. Data are
available at the national level by industry sector for in-scope 
industries and for all in-scope industries combined. These data 
represent all employment at establishments in a given revenue 
category; not all jobs in establishments with mixed green and nongreen
revenue are associated with production of green goods and services.

   The GGS-OCC estimates are based on the BLS output approach to
measuring green jobs: jobs in businesses that produce goods or provide
services that benefit the environment or conserve natural resources.
More information about the BLS green jobs initiative is available from
the green jobs homepage at www.bls.gov/green.

Concepts

Green goods and services are defined as goods and services that
benefit the environment or conserve natural resources. These goods and
services are sold to customers and include research and development,
installation, and maintenance services. Green goods and services fall
into one or more of the following five categories:

1.  Energy from renewable sources. Electricity, heat, or fuel
    generated from renewable sources. These energy sources include wind,
    biomass, geothermal, solar, ocean, hydropower, and landfill gas and
    municipal solid waste.

2.  Energy efficiency. Products and services that improve energy
    efficiency. Included in this group are energy-efficient equipment,
    appliances, buildings, and vehicles, as well as products and services 
    that improve the energy efficiency of buildings and the efficiency 
    of energy storage and distribution, such as Smart Grid technologies.

3.  Pollution reduction and removal, greenhouse gas reduction, and
    recycling and reuse. These are products and services that:

    --Reduce or eliminate the creation or release of pollutants or
      toxic compounds, or remove pollutants or hazardous waste from the
      environment.

    --Reduce greenhouse gas emissions through methods other than renewable 
      energy generation and energy efficiency, such as electricity
      generated from nuclear sources.

    --Reduce or eliminate the creation of waste materials; collect, reuse, 
      remanufacture, recycle, or compost waste materials or wastewater.

4.  Natural resources conservation. Products and services that conserve 
    natural resources. Included in this group are products and services 
    related to organic agriculture and sustainable forestry; land management;  
    soil, water, or wildlife conservation; and storm water management.

5.  Environmental compliance, education and training, and public awareness. 
    These are products and services that:

    --Enforce environmental regulations.

    --Provide education and training related to green technologies and
      practices.

    --Increase public awareness of environmental issues.

An establishment is generally a single physical location at which
economic activity occurs (e.g., store, factory, restaurant, etc.).
When a single physical location encompasses two or more distinct
economic activities, it is treated as two or more separate
establishments if separate payroll records are available and certain
other criteria are met.

An industry is a group of establishments that produce similar products
or provide similar services. For example, all establishments that
manufacture automobiles are in the same industry. A given industry, or
even a particular establishment in that industry, might have employees
in dozens of occupations. In the GGS-OCC data, similar establishments
are grouped into industries based on the 2007 North American Industry
Classification System (NAICS). More information about the NAICS is
available from www.bls.gov/bls/naics.htm.

An occupation is a set of activities or tasks that employees are paid
to perform. Workers are classified into occupations based on their job
duties and, in some cases, on the skills, education, and/or training
required. Workers with similar job duties are classified in the same
occupation, regardless of the industry in which they are employed.

Employees are all part-time and full-time workers who are paid a wage
or  salary. The estimates do not cover the self-employed, owners and
partners in unincorporated firms, household workers, or unpaid family
workers.

Industry coverage

The  GGS-OCC estimates are based on data for 333 of the nearly 1,200
detailed (6-digit) 2007 NAICS industries. BLS identified these 333
industries as  those in which businesses potentially produced green
goods or provided green services as their primary activity, based on
the definition of green goods and services above. The GGS-OCC scope
contains 20 percent of employment covered by state or federal
unemployment insurance, or about 19 percent of total U.S. employment.
A list of GGS-OCC in-scope industries is available in PDF format at
www.bls.gov/green/final_green_def_8242010_pub.pdf or in Excel format
at www.bls.gov/green/final_green_def_8242010_pub.xls.

The occupational classification system

The GGS-OCC occupational classifications are based on the Office of
Management and Budget’s Standard Occupational Classification (SOC)
system (www.bls.gov/soc/). The GGS-OCC estimates are based on data
collected under both the 2000 SOC and the revised 2010 SOC systems.
Almost all the occupations in this release are 2010 SOC occupations;
however, some are not. In some cases an occupation is a combination of
data reported for one or more occupations in the 2000 SOC and one or
more 2010 SOC occupations. Some of these combination occupations match
occupations in the 2000 SOC. In other cases, occupations from the two
structures were combined into a hybrid occupation that is not found in
either the 2000 or 2010 SOC. Some of these hybrid occupations have the
same title as a 2010 SOC occupation, but not the same content. These
occupations are marked with an asterisk (*) and given a temporary code
for the GGS-OCC data. For more information on how data collected under
the two structures were combined, including a downloadable concordance
between the SOC and GGS-OCC structures, see
www.bls.gov/oes/oes_ques.htm#Ques41.

Survey sample

The GGS-OCC estimates are based on a sample of approximately 93,000
private sector and federal, state, and local government establishments
in the 50 states and the District of Columbia. The GGS-OCC sample is
restricted to the 333 in-scope NAICS industries, and is a subset of
units in both the GGS sample and either the regular OES sample or a
supplement to the OES sample. Both the GGS and OES samples are drawn
primarily from the BLS Quarterly Census of Employment and Wages
(QCEW), which consists of businesses reporting to state unemployment
insurance (UI) programs.

The full GGS  sample of 120,000 establishments was selected by
stratifying the sampling frame by industry and state, and sampling
larger employers with a higher probability than smaller employers. The
GGS sample also includes an "environmental allocation" of approximately 
6,500 units, selected from a list of 13,000 establishments that BLS 
had previously identified as being involved in green activity.

The full OES sample consists of approximately 1.2 million business
establishments, collected in 6 semiannual survey panels over a 3-year
period. The GGS-OCC estimates are based on OES microdata collected
with reference dates of November 2011, May 2011, November 2010, May
2010, November 2009, and May 2009. The OES sample is stratified by
metropolitan or nonmetropolitan area, industry, and size. To provide
the most occupational coverage, larger employers are more likely to be
selected than smaller employers.

Approximately 41,300 establishments in the initial GGS sample
overlapped naturally with units in the 2009-2011 OES sample. In order
to increase the overlap between the two surveys, a swapping algorithm
was used to replace 23,400 nonoverlapping GGS units with similar units
that were already part of the OES sample. The GGS-OCC sample also
included 3,300 federal government units and a 25,000-unit supplement
to the OES survey, designed to cover agricultural industries excluded
from OES and to provide additional coverage of certain other
industries.

Data collection

Establishments in the GGS-OCC sample received two mail survey forms,
one for the GGS survey and one for the OES survey. Among GGS-OCC
sample units, the overall national response rates for the GGS survey
were 66.4 percent based on establishments and 59.9 percent based  on
weighted  employment. Response rates for the OES survey were 66.7
percent based on establishments and 65.3 percent based on weighted
employment. About 48.6 percent of sampled establishments, representing
42.6 percent of weighted sample employment, responded to both surveys.

The GGS survey asked establishments to report the percent of their
previous fiscal year’s revenue received from green goods and services.
Survey forms listed examples of green goods and services meeting the
BLS definition. Establishments that did not generate revenue, such as
government  establishments, nonprofits, or startups without positive
revenue, were asked to provide the percent of employment associated
with the production of green goods or provision of green services.

The OES survey form asked respondents to provide total employment for
the sampled establishment, as well as the number of workers, by
occupation, in each of 12 specific wage intervals. The wage intervals
were defined in terms  of both hourly rates and the corresponding
annual rates, where the annual rate for an occupation is calculated by
multiplying  the hourly wage rate by a typical work year of 2,080
hours. Full-time workers could be reported by either hourly rates or
annual salaries, depending on how the worker was paid.

Estimation methodology

Wage updating

The OES survey is designed to produce estimates at detailed levels of
geography, industry, and occupation by combining 6 panels of data
collected over a 3-year period. Wages for the most recent panel need
no adjustment. Wages for earlier panels are updated to the reference
period based on movements in the BLS Employment Cost Index (ECI) for
the most closely corresponding occupational category.

Nonresponse

GGS-OCC nonrespondents fell into three categories: (1) units that
responded to neither GGS nor OES; (2) units that responded to OES, 
but not GS; and (3) units that responded to GGS, but not OES. To
compensate for nonrespondents in categories 1 and 2, the weights of
responding units were adjusted through the use of nonresponse
adjustment factors (NRAFs). For nonrespondents in category 3, a
nearest neighbor hot deck procedure was used to impute occupational
staffing patterns, and a variant of mean wage imputation was used to
impute missing occupational wages.

Weighting and benchmarking

Sampled establishments were weighted to represent all establishments
for the GGS-OCC scope and reference period. Each establishment was
initially assigned a weight based on the reciprocal of its probability
of selection into the GGS sample. For units in the OES supplemental
sample, the GGS sampling weight was adjusted to account for its
probability of being subsequently subsampled in the supplement.
Weights were also modified by NRAFs in order to adjust for units that
did not respond to the GGS survey. Finally, the GGS-OCC data were
benchmarked to the average of QCEW employment levels for May and
November 2011.

Employment and wage estimation

The share of green revenue from GGS was used to divide establishments
into groups of businesses reporting no revenue from green goods and
services, all revenue from green goods and services, and a mix of
green and nongreen revenue. Occupational employment estimates were
calculated by multiplying each establishment's reported employment in
an occupation by the establishment's final weight, and summing the
resulting weighted employment across all establishments reporting the
occupation.

Because GGS-OCC wage data were collected by wage range rather than by
wage rate, additional information was required to estimate mean  and
median wages. Data from the BLS National Compensation Survey (NCS)
were used to calculate interval means for employees in each of the 12
wage intervals; these interval means were used in combination with the
reported data on occupational employment by wage interval to calculate
the GGS-OCC wage estimates.

GGS-OCC and GGS estimates

Although the GGS-OCC data have some similarities to the green jobs
estimates from the GGS survey, the two datasets also have important
conceptual differences and are not designed to be compared. Both the
GGS-OCC and GGS estimates are based on the BLS output approach to
measuring green  jobs, have the same industry scope, and have
overlapping samples. Both datasets also use the percent of each
sampled establishment’s revenue received from green goods and
services, as reported to the GGS survey, to produce their estimates.
However, the two sets of estimates use the green revenue  percentage
differently. The GGS survey multiplies each establishment's employment
by its green revenue share in order to produce estimates of the total
number of green jobs. For example, if an establishment that produces
both green and nongreen products employs 100 people and obtains 40
percent of its revenue from the sale of its green products, the GGS
survey would count 40 of that establishment's employees as green.

Unlike the GGS survey, the GGS-OCC program does not provide explicit
estimates of the number of green jobs. In particular, the GGS-OCC data
do not represent occupational breakdowns of the  green employment
estimates from the GGS survey. Instead, the GGS-OCC program uses the
green revenue shares from GGS to group establishments into categories
based on the percent of their revenue received from green goods and
services. For each revenue category, the GGS-OCC program provides
occupational employment and wage estimates for all employees in
establishments in that category. The two datasets also have different
reference periods: the GGS data represent 2010 annual averages, and
the GGS-OCC data have a November 2011 reference date. For more
information about the GGS survey, see www.bls.gov/ggs/.

Data available

The GGS-OCC data consist of employment, mean wage, and median  wage
estimates by occupation, presented for three groups of establishments:
those with none, all, or some, but not all, of their revenue from
green goods and services. Estimates are available at the national
level for 2-digit NAICS industries and for all industries combined.

For more information

Answers to frequently asked questions about the GGS-OCC data are
available at www.bls.gov/ggsocc/faq.htm. Detailed technical information 
about the GGS-OCC estimates is available in our Survey Methods and 
Reliability Statement at www.bls.gov/ggsocc/survey_methods.pdf.

Information in this release will be made available to sensory impaired
individuals  upon request. Voice phone: (202) 691-5200; Federal Relay
Service: (800) 877-8339.