Part B

Part B
Collection of Information Employing Statistical Methods

B.1. Respondent Universe
The electric power surveys collectively cover the entire range of companies involved in
the generation, transmission, distribution, and sales of electricity. Of the six surveys in
this package, three surveys are of the entire universe (or nearly the entire universe) based
on more exacting filing requirements given in those surveys. The remaining three
surveys are sample surveys. The respondent universe for each survey is:
•

EIA-411 – The target population for this annual census comprises all electricity
generators and electric utilities in the United States. The eight Regions of the
North American Electric Reliability Corporation (NERC) collect the data from the
target population units. Each Region assembles the required information using
input from the member electricity generators and electric utilities in its geographic
area. The Regions submit the compiled data to the NERC headquarters, where it
is consolidated and forwarded to the EIA.

•

Form EIA-826 – The target population for this monthly survey comprises all
U.S. electric utilities, electric service providers, and distribution companies.
Cutoff sampling is used to select the sample for the Form EIA-826, which
includes most of the investor-owned utilities (188), 4 Federal utilities, all electric
service providers (92), all distribution companies, and a sample of approximately
164 municipal, cooperative, State and political subdivision utilities that have sales
to end-use customers.

•

Form EIA-860 – The target population for this annual census comprises all
existing and proposed (for operation within 5 years) electric power plants that
have a total generator nameplate capacity of 1 megawatt or greater. Companies
complete the form for all the plants they operate. There are approximately 2,700
entities that operate and/or propose to operate about 5,500 facilities, containing
over 17,000 generators, who are required to file the Form EIA-860. The
respondents to this survey form the basis of the EIA electric power entity frame,
from which samples for other surveys are drawn.

•

EIA-860M – The target population for this monthly census comprises power
plants within the EIA-860 target population that have either (a) a new generator
scheduled to begin commercial operations within the next 12 months, or (b) an
existing generator scheduled for retirement within the next 12 months, or (c) an
existing generator undergoing modifications resulting in changes in capacity or
other major modifications that are scheduled to be completed within 1 month.
Respondents are the operators of the power plants where these new generators and

existing generators are located. Based on the number of plants putting new
generators into service in 2008 and 2009, the EIA estimates that in a typical
month the Form EIA-860M will be used to collect data from approximately 124
respondent entities.
•

Form EIA-861 – The target population for this annual census comprises
participants in the electric power industry involved in the generation,
transmission, or distribution of electricity in the United States and its territories.
Target population members include electric utilities, wholesale power marketers
(registered with the Federal Energy Regulatory Commission), energy service
providers (registered with the States), and electric power producers. There are
approximately 3,300 entities in the United States involved in the generation,
transmission, and distribution of electric energy. This survey serves as the
universe from which the sample for the Form EIA-826 is drawn.

•

Form EIA-923 – The target population for this annual census comprises all
electric plants in the United States that are connected to the electric power grid
and have a generating capacity of 1 megawatt or greater. While the target
population is defined in terms of plants, the respondents for the EIA-923 are
companies, which report data for the eligible plants they operate. There are
approximately 5,300 operating power plants (being reported by 2,800
respondents) for which data will be collected through Form EIA-923. Data will
be reported monthly for a sample of approximately 1,565 plants, although this
may be adjusted as the data are evaluated. Monthly respondents will report on
Schedules 1, 3, 4, and 5, plus Schedule 2 if their generating capacity is 50
megawatts or greater and they are fossil-fueled plants. At the end of the year, the
monthly respondents will report on Schedules 6 and 7, plus Schedule 8, if they
have a capacity of 10 megawatts or greater and they are steam-electric organicfueled plants. Those respondents who are not in the monthly frame will file
annually. They will file Schedules 1, 3, 4, 5, 6, and 7, plus Schedule 2 if their
capacity is 50 megawatts or greater and they are fossil-fueled plants, and
Schedule 8, if they have a capacity of 10 megawatts or greater and are steamelectric organic-fueled plants.

B.2. Statistical Methodology
To limit the burden on industry respondents, the two monthly surveys, the Form EIA-826
and the Form EIA-923, will be sent to only a sample of units in the target populations.
The samples will be cutoff samples, i.e., they will comprise all units with measures of
size larger than a predefined threshold. The cutoff sampling eliminates the monthly
reporting burden for smaller industry participants. Because smaller units have, in the
past, been responsible for a high percentage of reporting errors, the cutoff sampling may
also reduce the levels non-sampling error affecting the published estimates. (See Knaub
(2007) on cutoff sampling in general, Royall (1970) on model variance, and Knaub

(2001) on model bias and variance.) The remainder of this section provides detail on the
sampling and estimation methods used for the two sample surveys.
Form EIA-826 Sampling
For the Form EIA-826, the sample is composed of those utilities that typically sell most
of the electricity in each category (or end-use sector) in each State. The sample is made
up of
• all investor-owned utilities (IOUs), except for a few small IOUs in Alaska
• all energy service providers
• all Federal utilities
• all entities selling in the public transportation sector
• a sample of the municipal and cooperative utilities.
The frames for Schedule B (energy service providers) and Schedule C (distribution
companies) are not always complete, as information from the States on these entities is
not always available in a timely manner. In these cases, the two types of respondents are
reconciled at the State level and added to the State totals as residuals. (Classical ratio
estimation can be used for variance estimation. See Knaub (1991), pages 776 and 777,
“Incompletely Specified Auxiliary Data.”) A zero-intercept, ratio model (see Royall and
Cumberland, 1978) is used to estimate total sales and revenue by end-use sector and
State. The sample eliminates the smaller respondents, thus reducing burden and reducing
the source of non-sampling errors.
The Form EIA-826 sample design and estimation procedures employ a linear regression
model to represent the relationship between the respondent’s annual data value (e.g.,
sales) from the prior year and the corresponding monthly value for the current month.
The prior year’s annual data come from the Form EIA-861. Data values for units not in
the sample are estimated from the prior year’s annual data and the estimated parameters
of the regression model. Data from sample units for which there is no historical Form
EIA-861 data (e.g., units new to the target population) are not used to estimate the
relationship between the prior year’s annual value and the current monthly value. The
reported current monthly data are, however, used in estimating totals for publication
groups. (See Knaub (2002).) If a sample unit’s annual data are deemed reliable, and its
Form EIA-826 (monthly) data are considered unreliable, the annual data are used (as for
the non-sampled units) to impute the monthly Form EIA-826 data. As mentioned above,
a census is performed within the Form EIA-826 for the utilities and power marketers or
energy service providers (ESP) data, and their totals are added to the estimated (imputed)
entities to obtain the estimates for the entire universe.
Form EIA-826 Monthly Sample Selection from the Form EIA-861 Annual Frame:
The monthly cutoff sample thresholds for the Form EIA-826 were originally selected
based on the criterion of having estimated relative standard error (RSE) values less than 1
percent for all publication groups. The RSE is a percentage measure of the precision of a
survey statistic and is used in part as one way to measure sampling error induced by

sampling. RSEs are estimated using model-based predicted monthly values of the
quantities of interest (revenues, sales, etc.) along with the corresponding annual (Form
EIA-861) data for the units not in the monthly sample. Threshold values for the cutoff
sampling have been adjusted over time to maintain low RSEs for the published estimates.
For 2008, the adjustments are based on a preliminary run of the regression imputation
procedure using 2006 preliminary monthly data along with annual data from 2005. The
cutoff threshold is revised downward (i.e., one or more additional sample units are added)
for a sampling stratum (State crossed by industry sector) when both of the following
criteria hold for either sales or revenue estimates:
1.) At least 1 month produced an RSE greater than 5 percent for a given
State/sector.
2.) At least 2 other months had an RSE greater than 2 percent for the same
State/sector as in item #1.
These criteria were chosen to maintain reasonably low RSEs for the published estimates
without adding substantial burden to respondents or increasing the monthly processing
burden for the EIA. The above criteria help ensure that the sample is not increased due to
one or two questionable data points. Threshold values are only revised downward for
strata that appear consistently prone to high variability.
The adjustments resulted in the addition of 20 respondents to the Form EIA-826 monthly
sample. Of these, three additions are due to sales RSEs only, four are due to sales and
revenue RSEs, and 13 additions are due to revenue RSEs only. In future years, similar
procedures will be used to adjust the cutoff sample threshold values, as needed, in order
to maintain the reliability of the estimates while minimizing costs and respondent burden.
Form EIA-923 Sampling
One of the goals of the new Form EIA-923 sample selection process is to reduce the sample
size from the current Forms EIA-906/920 sample. Not only does this reduce respondent
burden, but it also allows the EIA survey staff to focus its resources on a smaller sample to
ensure a higher quality of data. A reduction in sample size is especially important in the
commercial and industrial sectors due to sometimes questionable data quality and the difficulty
in collecting data from many of the smaller facilities.
The cutoff sampling process for the Form EIA-923 sample is similar to the one described
above for the monthly Form EIA-826 sample. A preliminary run of the regression imputation
procedure was performed using 2006 finalized annual data. Monthly reported values plus
annual values prorated across months then form the census for the year chosen. Gross
generation is the main focus of the sample selection process and its high correlation with other
data elements on the Form EIA-923 should ensure good results for other reported values.
Further experiments to adjust the cutoff sampling thresholds based on other data requirements
will be performed as the opportunity permits. Future study should especially focus on such

variables as volumes and costs of fuels received by respondents, in order to evaluate the effects
of the new sampling procedures on the ability of the EIA to impute data for respondents who
formerly reported monthly on the EIA/FERC-423 forms.
Sampling parameters are assigned to each sampling stratum. The strata are defined by facility
type, energy source, and geographic region. (See "publication groups" in Knaub (1999).) For
instance, one stratum is identified as electric utilities burning coal in the South Atlantic Census
Division. The types of stratification groups are briefly described below.

Facility Type Classification for Form EIA-923
The four facility type categories comprise seven sectors for which data are collected. These
four categories, which correspond to the facility type classifications published in the Electric
Power Monthly (EPM), are (1) electric utilities, (2) independent power producers, (3)
commercial facilities, and (4) industrial facilities. Table 8 below shows the seven sectors.
(Combined Heat and Power Plant is abbreviated CHP.)
Table 8. Facility Types
Sector Classification Sector Classification Description
Number
1
Regulated Electric Utility
2
IPP (Non-CHP)
3
IPP (CHP)
4
Commercial (Non-CHP)
5
Commercial (CHP)
6
Industrial (Non-CHP)
7
Industrial (CHP)

Facility Type Stratification
Group
Electric Utilities
Independent Power Producers
Independent Power Producers
Commercial Facilities
Commercial Facilities
Industrial Facilities
Industrial Facilities

Energy Source Classification for Form EIA-923
The 14 energy source categories, which correspond to the energy source classifications
published in the EPM, are aggregations of the 36 different fuel types for which data are
collected on the survey. Table 9 gives the 14 energy source categories and the corresponding
stratification categories. The energy source codes are defined in the instructions for
completing Form EIA-923. (See Appendix C.)
Table 9. Energy Source Aggregations
Reported Energy Source Code
NG
NUC

Energy Source Stratification
Group
Natural Gas
Nuclear

HPS 1
WAT
PC
GEO
SUN
WND
BFG, OG, PG
WDL, WDS, BLQ
OTH, MSN, TDF, PUR
BIT, LIG, SC, SUB, WC
RFO, DFO, JF, KER, OO, WO
AB, LFG, MSB, OBG, OBL, OBS, SLW

Pumped Storage
Conventional Hydroelectric
Petroleum Coke
Geothermal
Solar
Wind
Other Gas
Wood
Other Sources
Coal
Petroleum
Waste

Geographic Regions Classification for Form EIA-923
The 10 geographic sampling groups correspond to 10 modified Census division regions
published in the EPM. The States assigned to each division are shown in Table 10.
Table 10. State/Census Division Aggregations
States
Modified Census Divisions
AK, HI
Pacific Non-Contiguous
NJ, NY, PA
Mid-Atlantic
CA, OR, WA
Pacific Contiguous
AL, KY, MS, TN
East Central
AR, LA, OK, TX
West Central
IL, IN, MI, OH, WI
East North Central
CT, ME, MA, NH, RI, VT
New England
IA, KS, MN, MO, NE, SD, ND
West North Central
AZ, CO, ID, NT, NV, NM, UT, WY
Mountain Region
DE, DC, FL, GA, MD, NC, SC, VA, WV
South Atlantic
Sample Selection Criteria for Form EIA-923
The Form EIA-923 sample is chosen to provide reasonably accurate results for multiple
attributes (published aggregate numbers) while minimizing the burden on the industry and the
Federal government. The following five steps are used in selecting plants for the monthly
sample:
1) Select preliminary cutoff samples based on nameplate capacity values.
2) Add sample units, where necessary, based on generation, consumption and stocks.
3) Add sample units, where necessary, to provide adequate sample counts for estimation
groups.

1

Pumped Storage facilities do not actually report energy source code HPS, rather they report energy source code WAT
combined with a prime mover code of PS to differentiate them from conventional hydroelectric facilities. The energy
source is renamed to HPS for simplicity sake only.

4) Add sample units, where necessary, to reduce relative standard errors (RSEs) of key
estimates to acceptable levels.
5) Add other facilities, based on special-case criteria.
The first three steps are designed to ensure adequate coverage of the target population by
including all of the largest contributors to key data elements. The fourth step helps ensure that
the published estimates will meet reasonable reliability standards, which is the key goal, given
acceptable resource expenditure. The final criterion covers special cases, as described below.
Facilities in the target population that meet any one of the sample selection criteria applied at
any of the five steps are included in the final sample. Further, any additional prime movers and
energy sources used by a sample facility are also included in the sample even if individually
they did not meet any of the sample selection criteria. Each sample facility reports data for all
combinations of prime mover and fuel source each month. All nuclear and pumped storage
facilities are included in the monthly sample. The remainder of this section provides further
detail on the sampling steps.
Step 1: Select Cutoff Samples Based on Nameplate Capacity. Initially, pre-determined
capacity coverage percentages are tested to ensure a certain proportion of operational Form
EIA-860 capacity is covered within each sampling group. Stand-by and back-up generators are
not included in the operational capacity totals when data are aggregated to the level of prime
mover, and only the largest consumed fuel source for each generator is used in identifying the
sample groupings. Different coverage percentages are selected for each facility classification,
and are applied to all regions and energy sources within each classification. When the capacity
cutoff percentage yields a capacity cutoff of less than 25 megawatts, then a default value of 25
megawatts is used instead. Otherwise, the percentages of capacity included in the sample are
listed below.
1)
2)
3)
4)

Electric utilities – 70 percent
Independent power producers – 70 percent
Commercial facilities – 50 percent
Industrial facilities – 50 percent.

Step 2: Add Units Based on Generation, Consumption, and Stocks. Facilities accounting for
large percentages of actual past reported gross generation, fuel consumption, or fuel stocks, are
added to the sample, even if their nameplate capacities fall below the capacity coverage
percentage cutoff.
Step 3: Add Units to Ensure Adequate Sample in Estimation Groups. Estimation strata
identical to those currently employed in the Form EIA-906/920 regression imputation system
are examined. Units below the threshold value are added to any group with fewer than 10
usable observations, until the usable count is brought up to 10.
Step 4: Add Sample to Meet Reliability Standards. Weighted multiple regressions, identical to
those currently employed in the Form EIA-906/920 imputation system, are run, and relative
standard error (RSE or CV) estimates are calculated for each publication group by month. An

additional diagnostic measure, the RSESP, is calculated to indicate the adequacy of the
regression model fit. Limits for both measures (RSE and RSESP) are set individually for each
facility classification and applied to all energy sources for the U.S. total for each classification.
If one or both of the error measures falls outside of the limits, the next largest facilities, ranked
by gross generation, are included until the RSE/RSESP's are brought into a reasonable range.
It is important to note that if only the RSESP estimate is out of range, then it is difficult to
lower the estimate of RSESP based on sampling alone. In these cases, a change in modeling
may be necessary. The RSE/RSESP data quality limits are outlined below.
1)
Electric utilities – RSE less than 5 percent and RSESP less than 20 percent
2)
Independent power producers – RSE less than 5 percent and RSESP less than 20
percent
3)
Commercial facilities – RSE less than 10 percent and RSESP less than 30 percent
4)
Industrial facilities – RSE less than 10 percent and RSESP less than 30 percent.
Step 5: Add Special Cases. Finally, additional facilities are added to the sample as necessary.
These include storage-only facilities (used in estimating stocks); new facilities for which the
EIA has no prior-year’s annual data for use in regression imputation; and any large, easy to
survey facilities which the survey staff identifies as being desirable in the sample.
EIA-923 Sampling Results
The new sampling methodology implemented with Form EIA-923 results in a 24-percent
decrease in the number of sampled facilities, as shown in Tables 11 and 12. This reduces the
amount of reported gross generation by approximately 7 percent. The lower sample coverage
may increase the number of table cells in EIA publications for which estimates cannot be
published due to high sampling variability. It is expected, however, that the new procedures
will decrease the levels of non-sampling error affecting the published estimates.
Table 11. Form EIA-923 Sample Coverage by Facility Type
Facility
Total
Current Sample
Proposed Sample
Type
Count
Count

Percent Percent
by
by
Count Volume
28
90

Sample
Count
Change
in
Percent

Regulated
Utilities

2,600

Percent Percent Count
by
by
Count Volume
1,018
39
97
732

Independent
Power
Producers
Industrial
Facilities

1,868

733

39

95

624

33

89

-15

592

190

32

80

130

22

64

-32

-28

Commercial
Facilities
Total

206

52

25

62

34

17

63

-35

5,266

1,993

38

96

1,520

29

89

-24

Table 12. Form EIA-923 Sample Coverage by Energy Source

Table 13 provides a comparison of the relative standard errors (RSEs) for State levelEnergy
Total
Current Sample
Proposed Sample
Sample
Source
Count
Count
Change
Count Percent Percent Count Percent Percent in
by
by
by
by
Percent
Count Volume
Count Volume
Coal
280
200
71
98
156
56
89
-22
Geothermal
49
26
53
92
16
33
70
-38
Hydroelectric 1,332
349
26
84
198
15
67
-43
Natural Gas
1,540
583
38
91
435
28
81
-25
Nuclear
65
65
100
100
65
100
100
0
Other Gas
59
41
69
96
27
46
78
-34
Other Sources
115
61
53
92
53
46
86
-13
Petroleum
1,025
333
32
98
290
28
94
-13
Petroleum
28
17
61
97
16
57
88
-6
Coke
Pumped
39
39
100
100
39
100
100
0
Storage
Solar
11
10
91
99
11
100
100
+10
Waste
232
8
3
44
30
13
54
+275
Wind
271
131
48
92
81
30
76
-38
Wood
220
130
59
89
103
47
73
-21
Total
5,266
1,993
38
96
1,520
29
89
-24
publication groups under the current sample and the proposed sampling procedures. The
within-State groupings include breakouts by plant type and energy source. The counts shown
in the table cover the entire year, so groups that had RSEs over the labeled amount in any 1
month are included in the final number. Note that the current criterion for not publishing an
official statistic is that the corresponding RSE is larger than 50 percent.
Table 13. Form EIA-923 RSE Comparisons for Current vs. Proposed Sample
Type
Total RSE > 50 percent RSE > 20 percent RSE > 10 percent
Current Sample
1,825 417
611
766
Proposed Sample 1,825 545
754
952

Graphic Representations of RSE/RSESP

For analysis purposes, when deciding on the sampling criteria to be used in order to provide
customers with reasonably accurate data in a reasonable time frame with acceptable cost to the
EIA and burden on the industry, graphs were used to display RSE and RSESP values and gross
generation totals for the entire United States by facility type. As part of the process of
determining the sample, reliability estimates computed from a sample of data collected in
previous years were examined. The U.S. level was studied, but State level data and Census
Division data were also considered. (Table 13 above shows data collected at the State level.)
Following is an example of a U.S. level graph showing the range of estimated RSE and
estimated RSESP values that pertained to each monthly gross generation estimate in 2006.
This shows acceptable indications of accuracy for such a sample, for industrial facilities. It is
anticipated that with such a reduced sample size, future data collections will have also have a
reduced non-sampling error.
Figure 2 – U.S. Level - Industrial Facilities – All Energy Sources

Table 14 displays a summary of the threshold values for nameplate capacity that were used for
selecting cutoff samples of facilities in the 2006 frame. Facilities new to the frame in 2007
will be collected monthly regardless of their capacities due to a lack of annual regressor data
for imputation. These cutoff values, given by facility type and energy source, were calculated
using the same capacity coverage percentages described above, except that the coverage
percentages pertain to strata representing higher levels of aggregation. Overall, the share of
capacity that the monthly sample covers by fuel type and facility type are shown in Table 15.
Facility types were aggregated into three strata: regulated utilities, independent power
producers, and commercial/industrial facilities. Energy sources were aggregated into only
coal, natural gas, conventional hydroelectric, petroleum, nuclear, pumped storage, and all other
types. These cutoff levels may vary as the data are evaluated in the future.

Table 14. Form EIA-923 Capacity Cutoffs (megawatts)
Natural
Facility Type
Coal
Gas
Hydroelectric Petroleum Other
Regulated Utilities
860
380
150
130
90
Ind. Power Producer
620
590
25
470
30
Commercial/Industrial
50
90
40
25
50

Pumped
Nuclear Storage
Census Census
Census Census
Census Census

Table 15. Form EIA-923 Capacity Coverage (percent)
Natural
Pumped
Facility Type
Coal
Gas
Hydroelectric Petroleum Other Nuclear Storage
Regulated Utilities
90
83
72
77
92
100
100
Independent. Power
Producer
88
83
66
84
74
100
100
Commercial/Industrial
68
65
75
57
67
100
100
REFERENCES:
The regression estimation/imputation procedures used for the Form EIA-826 and Form
EIA-923 are documented and discussed in the on-line statistics journal, InterStat, in the
following articles:
•
•
•

“Using Prediction-Oriented Software for Survey Estimation,” at the following URL:
http://interstat.stat.vt.edu/interstat/articles/1999/abstracts/g99001.html-ssi
“Using Prediction-Oriented Software for Survey Estimation - Part II: Ratios of
Totals,” at the following URL:
http://interstat.stat.vt.edu/interstat/articles/2000/abstracts/u00002.html-ssi
“Using Prediction-Oriented Software for Survey Estimation - Part III: Full-Scale
Study of Variance and Bias,” at the following URL:
http://interstat.stat.vt.edu/interstat/articles/2001/abstracts/u01001.html-ssi.

The method described in these articles is generally useful for both small area estimation
and imputation, with adjustments as described in those documents. Additional
documentation and references include:
(1) “Model-Based Sampling, Inference and Imputation,” available on the EIA Web site
at: http://www.eia.doe.gov/cneaf/electricity/forms/eiawebme.pdf
(2) “Weighting in Regression for Use in Survey Methodology," InterStat, available at:
http://interstat.stat.vt.edu/InterStat/ARTICLES/1997/abstracts/A97001.html--ssi.
(3) “Some Applications of Model Sampling to Electric Power Data,” ASA
Proceedings of the Survey Research Methods Section, available at:
www.amstat.org/sections/SRMS/proceedings/papers/1991_133.pdf

(4) Royall, R.M., and W.G. Cumberland (1978), "Variance Estimation in Finite
Population Sampling," Journal of the American Statistical Association, 73, 351-358
(5) “The Classical Ratio Estimator,” InterStat, available at:
http://interstat.statjournals.net/YEAR/2005/abstracts/0510004.php
(6) “Cutoff Sampling and Inference,” InterStat, available at:
http://interstat.statjournals.net/YEAR/2007/abstracts/0704006.php.

B.3. Methods to Maximize Response Rates
For all of the EIA electric power respondents, the response rates are close to or equal to
100 percent. For 2006 annual data, all 7,914 annual respondents (aggregated across all
surveys) submitted their data and typically only about 3-7 out of 2,291 monthly 2007 data
respondents did not submit their data in any given month. To maximize response rates,
the EIA forms have been designed and the instructions have been written to be clear and
concise to help the respondent complete the forms. Data that are not expected to change
from year-to-year or month-to-month are pre-populated on the forms. Forms and/or
notifications are mailed or e-mailed early to maximize the time that respondents have to
complete the surveys. As noted, the EIA Internet Data Collection (IDC) System makes
forms available on-line as soon as respondents obtain a secure ID and password. Given
the high IDC use rate in 2007 (80 percent of the annual reports and approximately 91
percent of the monthly reports are reported by IDC); most of those respondents will
merely log on in the next data collection period and access their required forms. Form(s)
due dates are the same each period so that respondents can schedule their completion
activities. The notification and due dates for each survey are provided in Table 6.
The non-respondents are contacted by e-mail, telephone, and letter to request data
submission until an insignificant non-response rate is obtained. Follow-up letters and emails citing failure to file the required form are mailed to all non-respondents. If no
response occurs as a result of the letters, additional correspondence is sent from the
Office Director and Administrator, if necessary, to higher level management officials
requesting submission of the appropriate data. Statistical imputation fills any gaps
created by the small amount of non-response.
Respondents who file via the IDC System are given the opportunity to either correct or
explain unusual data during their submission. The explanations are reviewed by the EIA
staff. Respondents are called if further clarification is needed. For those respondents that
do not file via the IDC, but rather on a hardcopy of the form, telephone calls are made to
confirm corrections or clarifications of any unusual data.
In addition, the EIA has recently developed an improved centralized frame system which
affords all survey staff almost immediate knowledge of changes in plant ownership
and/or contacts; such changes contributed to non-response in the past. The new system is

integrated with the IDC System so that access can be given to new owners and/or
contacts quickly.

B.4. Tests of Procedures
The electric power surveys are established continuing surveys. Although the Form EIA923 is new, the data being collected are the same as were collected through several other
forms that have been discontinued. The Form EIA-860 was revised to include some data
from a discontinued form as well. Modifications to the existing forms were made by the
EIA staff. The testing of these new and revised forms has several parts. First, the forms
were reviewed by internal EIA subject matter and survey methodology experts. The
second phase of the testing involved sending draft forms to representatives of the major
segments of the electric power industry. Finally the survey forms were tested with actual
volunteer survey respondents. They were asked to review the forms and debriefed by
EIA to make sure they understood the concepts being measured, could successfully
navigate the forms, and had the data in their business records. Changes were made at all
stages of testing to incorporate feedback.

B.5. Forms Consultation
During 2006, the Electric Power Division met with a variety of stakeholders to make
them aware of the general proposals for form changes and to elicit their suggestions,
concerns and needs. The following is a list of the organizations with whom the EIA met.
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American Council for an Energy Efficient Economy
American Public Power Association
American Statistic Association
DOE, Office of Electricity Delivery and Energy Reliability
DOE, Office of Fossil Energy
Edison Electric Institute
Electricity Consumers Resource Council
Electric Power Supply Association
Federal Energy Regulatory Commission
National Association of Regulatory Utility Commissioners
National Mining Association
National Rural Electric Cooperative Association
North American Electric Reliability Corporation
2007 EIA Energy Outlook, Modeling, and Data Conference.

For additional information concerning these surveys, please contact Jorge Luna-Camara
at 202-586-3945 or at [email protected]. For information concerning this request

for OMB approval, please contact the agency Clearance Officer, Jay Casselberry, at 202586-8616 or at [email protected].