Year	billion cubic meters
1995	1.98
1996	1.9514
1997	1.9228
1998	1.8942
1999	1.8656
2000	1.837
2001	1.8108
2002	1.7846
2003	1.7584
2004	1.7322
2005	1.706
2006	1.6744
2007	1.6428
2008	1.6112
2009	1.5796
2010	1.548
2011	1.5366666667
2012	1.5253333333
2013	1.514
2014	1.571
2015	1.448
2016	1.452
2017	1.397
2018	1.39
2019	1.358
2020	1.328