Research on the Definition of Economic Limits for the Development of Unconventional Natural Gas under New Situations

Table 2

Outputs of three nnconventional natural gases in recent 10 years (unit: 100 million m³) (The data is collected by the author according to courses as historical reports of the National Energy Administration and the National Bureau of Statistics as well as annual reports of the companies. Since the tight gas outputs in 2017 and 2018 are highly disputable, the means are adopted).

Year	2009	2010	2011	2012	2013	2014	2015	2016	2017	2018
CBM	7	14	23	27	30	35.4	44	74.8	70.2	72.6
Shale gas	—	—	—	—	2	13	44.7	78.8	91	108.81
Tight gas	150	160	256	320	340	370	400	421	446	470