# Presentation: 709925

## EIA-914: Estimating Monthly Natural Gas Production with a 90% Cut-Off Sample Survey 

- ASA Committee on Energy Statistics
- Washington, DC
- October 28, 2004
- John Wood
- Director, Reserves and Production Division, OOG

## 
Substantially improve both the quality and timeliness of our monthly natural gas production estimates for key States and at the National level. 
Our target is to have releasable numbers 60 days after the close of a report month with a sampling error at the national level within  1% and within 1% to 5% for six areas; Texas, Federal Gulf of Mexico, Oklahoma, Wyoming, New Mexico, and Louisiana.

**Substantially improve both the quality and timeliness of our monthly natural gas production estimates for key**** States and at the National level.**** **
**Our target is to have releasable numbers 60 days after the close of a report month with a sampling error at the national level within  1% and within 1% to 5% for six areas; Texas, Federal Gulf of Mexico, Oklahoma, Wyoming, New Mexico, and Louisiana.**

-  EIA-914 Objectives

**Notes:**
These are the six largest producing areas in the lower-48 States.

## Questions for the Committee

- 1.  We would like your comments on our interpretation and analysis of the data and our approach to modeling or estimating the production from non-sampled operators.
- 2.  Do you have any recommendations on handling non-response or apparent errors in reporting for the large operators?  (Top 5 operators in Texas have roughly 25 percent of production.)
- 3.  Any suggestions on detecting or handling outliers and overly influential operators and how we should deal with these when making estimates?

## Slide 4

**Notes:**
1  Skewed production distribution with large operators having most of the lower-48 production. 
2. Top 5 operators have 28%
3. Top 14 operators have 51%
4. Top  78 operators have 75%
5. Top 223 operators have 90%
6. The rest of the roughly 15,000 operators have the remaining 10%

## How Many Operators for 90% Coverage?

- 1

- 2

- 3

- 4

- 5

- 284 or 337?

- 5 Sorts and Selections

## Slide 6

## Slide 7

## Slide 8

**Notes:**
1. Calibration year 2000.

## Slide 9

## Slide 10

**Notes:**
Top 15 operators, the first two quartiles, down 5%.
 Next 188 operators up a couple of percent for 2 years.
 Again, the 10% group is up 17% after 2 years. 

## Slide 11

## General Model Relationship

- Total Production

- Sum of all Operators

- Sum of Surveyed Operators Used to Estimate Non-Surveyed Operators

- Sum of Surveyed Operators Not Used to Estimate Non-Surveyed Operators

- Sum of Non-Surveyed Operators

## Estimating the Non-Surveyed Operators

- Sum of Surveyed Operators Used to Estimate Non-Surveyed Operators

- Estimated Sum of Non-Surveyed Operators

## Accounting For a Declining Trend

- Calculated Ratio

- Fit Parameter

- Time

## Estimation Model

- Sum of Surveyed Operators Used to Estimate Non-Surveyed Operators

- Sum of Surveyed Operators Not Used to Estimate Non-Surveyed Operators

- Modeled Sum of Non-Surveyed Operators

## Slide 16

## Ratio and Trend Parameters

- Calibration
- Year		   *R**m*		   *A**m*
- 1997		0.1111		0.0026
- 1998		0.1110		0.0053
- 1999		0.1107		0.0074
- 2000		0.1109		0.0089
- 2001		0.1107		0.0119
- 2002		0.1108
- 2003		0.1109 (partial year)

## Slide 18

## Slide 19

## Add a Slope Term to Predict the Trend

- Slope = 0.0022 per year

## Slide 21

## Got Questions?

## Slide 23

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## Slide 25

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## Slide 27

## Slide 28

## Slide 29

## Slide 30

## Slide 31

## Ratio and Trend ParametersExcluding the Top 5 Operators

- Calibration
- Year		   *R**m*		   *A**m*
- 1997		0.1597		0.0035
- 1998		0.1616		0.0056
- 1999		0.1614		0.0066
- 2000		0.1614		0.0072
- 2001		0.1588		0.0100
- 2002		0.1579
- 2003		0.1537 (partial year)

## Slide 33

**Notes:**
First Quartile, Top 5 operators, drops 10% in 2 years.
 Second quartile up most of 2 years, but back down to starting percentage at end of 2 years.
 Third quartile down some over 2 years
 Fourth Quartile up about 7% over 2 Years.
 10% group up 17% 

## Slide 34

## Calculating the Ratio Excluding the Top 5 Operators

## Ratio Calculated in the Calibration Year

- Sum of Surveyed Operators Used to Estimate Non-Surveyed Operators

- Sum of all Operators

- 12 Month Sum