HOUSTON, July 24 (Xinhua) — Working gas storage in the contiguous United States was 3,075 billion cubic feet in the week ending July 18, a net increase of 23 billion cubic feet from the previous week, the U.S. Energy Information Administration (EIA) said in a report on Thursday.

The total working gas storage declined 4.7 percent from this time last year, but was 5.9 percent above the five-year average, according to the EIA’s Weekly Natural Gas Storage Report.

U.S. working gas storage usually begins to decline in November and continues falling through April, coinciding with the end of the heating season, according to previous data.

Working gas is defined as the amount of natural gas stored underground that can be withdrawn for use. Its storage capacity can be measured in two ways: design capacity and demonstrated maximum working gas capacity.

The contiguous United States consists of the country’s 48 adjoining states plus the District of Columbia, and excludes the non-contiguous states of Alaska and Hawaii and all offshore insular areas.