Last year, the last full year for which statistics are available, U.S. production averaged 25.7 billion cubic feet per day and Canada produced an average of 14 billion cubic feet per day, the Energy Department's Energy Information Administration said.
Nearly all of the U.S. production came from five areas in the central United States and approximately 15 percent of Canada's production came from the Muskwa-Otter Park shale formation in northern British Columbia and the Montney basin, spread out over British Columbia and Alberta, the agency said.
The EIA, in a report Wednesday, said China is the only country outside of North America that has reported lucrative deposits of shale natural gas. Shale gas in China, however, accounts for 1 percent of its total natural gas production, compared with 39 percent for the United States and 15 percent for Canada.
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