Year	billion cubic meters
1998	1.2848
1999	1.3362904762
2000	1.3866809524
2001	1.4381714286
2002	1.4558285714
2003	1.4734857143
2004	1.4911428571
2005	1.5088
2006	1.5198
2007	1.5308
2008	1.5418
2009	1.5269109091
2010	1.5120218182
2011	1.4971327273
2012	1.4691186364
2013	1.4411045455
2014	1.4130904545
2015	1.3850763636
2016	1.3570622727
2017	1.3290481818
2018	1.3010340909
2019	1.2724
2020	1.27302