HOUSTON, March 28 (Xinhua) -- Working natural gas storage in the contiguous United States was 1,107 billion cubic feet (about 31.35 billion cubic meters) in the week ending March 22, a net decrease of 36 billion cubic feet from the previous week, the U.S. Energy Information Administration (EIA) said in a report on Thursday.

At 1,107 billion cubic feet, total working gas storage decreased by 20.5 percent from this time last year, or 33.2 percent below the five-year average, but still within the five-year historical range, according to EIA's Weekly Natural Gas Storage Report.

The storage of working natural gas will turn to increase in late April and will continue to grow into early November when heating season starts in the country, according to previous data.

Working natural gas is defined as the amount of natural gas stored underground that can be withdrawn for use.

Working natural gas storage capacity can be measured in two ways: design capacity and demonstrated maximum working gas capacity.

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