Types of Possible Survey Errors in Estimates Published in the Weekly Natural Gas Storage Report

Release date: March 1, 2016

The U.S. Energy Information Administration (EIA) collects and publishes natural gas storage information on a monthly and weekly basis. The Form EIA-191, Monthly Underground Natural Gas Storage Report, is a census survey that collects field-level information from all underground natural gas storage operators in the United States known to EIA. EIA also collects weekly information about working natural gas levels from a sample of natural gas storage operators completing the Form EIA-912, Weekly Underground Natural Gas Storage Report. The EIA-191 and EIA-912 surveys are the basis for the EIA's Weekly Natural Gas Storage Report (WNGSR).

This document lists types of potential errors in EIA estimates published in the WNGSR. Survey errors are an unavoidable aspect of data collection. Error is inherent in all collected data, regardless of the source of the data and the care and competence of data collectors. The type and extent of error depends on the type and characteristics of the survey.

The analyses in this document is based on techniques found in the statistical literature. Groves et al. (2011), Biemer and Lyberg (2003), and Weisberg (2009) all presented concepts and issues involving evaluations of total survey error. Possible survey errors in estimates published in the WNGSR may include sampling error, coverage error, nonresponse error, adjustment error, measurement error, and processing error.