text: U.S. Energy Information Administration, "Petroleum & Other Liquids: Effects of Removing Restrictions on U.S. Crude Oil Exports," September 1, 2015, http://www.eia.gov/analysis/requests/crude-exports/ (accessed July 1, 2016). See also U.S. Energy Information Administration, "Assumptions to the Annual Energy Outlook 2015," September 2015, https://www.eia.gov/forecasts/aeo/assumptions/pdf/introduction.pdf (accessed July 22, 2016): "Estimated ultimate recovery per shale gas, tight gas, and tight oil well is 50% higher and well spacing is 50% closer (or the number of wells left to be drilled is 100% higher) than in the Reference case. In addition, tight oil resources are added to reflect new plays or the expansion of known tight oil plays, and the estimated ultimate recovery for tight and shale wells increases by 1% per year more than the annual increase in the Reference case to reflect additional technology improvements. Also includes kerogen development; and undiscovered resources in the lower 48 offshore and Alaska, and shale gas and coalbed resources in Canada that are 50% higher than in the Reference case."