Year	billion cubic meters
1990	13.291
1991	13.2096
1992	13.1282
1993	13.0468
1994	12.9654
1995	12.884
1996	12.862
1997	12.84
1998	12.818
1999	12.796
2000	12.733
2001	12.9458461538
2002	13.1586923077
2003	13.3715384615
2004	13.5843846154
2005	13.7972307692
2006	14.0100769231
2007	14.2229230769
2008	14.4357692308
2009	14.6486153846
2010	14.8614615385
2011	15.0743076923
2012	15.2871538462
2013	14.286
2014	16.473
2015	18.66
2016	19.05
2017	19.38
2018	19.64
2019	20
2020	20.31