History: Total production and Alaska: Energy Information Administration (EIA), Natural Gas Annual 2000, DOE/EIA-0131(2000) (Washington, DC, October 2001). Offshore, associated-dissolved, and conventional: EIA, U.S. Crude Oil, Natural Gas, and Natural Gas Liquids Reserves, DOE/EIA-0216. Unconventional: EIA, Office of Integrated Analysis and Forecasting. 2001 and projections: Table A15. Note: Unconventional gas recovery consists principally of production from reservoirs with low permeability (tight sands) but also includes methane from coal seams and gas from shales.