IEA (2020), Absolute and relative change in natural gas gross deliveries in selected OECD countries, 2018-2019, IEA, Paris https://www.iea.org/data-and-statistics/charts/absolute-and-relative-change-in-natural-gas-gross-deliveries-in-selected-oecd-countries-2018-2019, Licence: CC BY 4.0