Proven Reserves, Natural Gas (in Billions) (M3)
Definition :

Estimated quantities of all hydrocarbons statistically defined as natural gas, expressed in terms of cubic meter. They consist of those quantities of natural gas (associated and non-associated) which by analysis of geoscience and engineering data can be estimated with reasonable certainty to be commercially recoverable, from a given date forward, from known reservoirs and under defined economic conditions, operation methods and government regulations.