Year	billion cubic meters
1985	0.29
1986	0.30228
1987	0.31456
1988	0.32684
1989	0.33912
1990	0.3514
1991	0.3637
1992	0.376
1993	0.3952444444
1994	0.4144888889
1995	0.4337333333
1996	0.4529777778
1997	0.4722222222
1998	0.58
1999	0.614
2000	0.648
2001	0.682
2002	0.716
2003	0.75
2004	0.784
2005	0.818
2006	0.818
2007	0.818
2008	0.818
2009	0.818
2010	0.818
2011	0.818
2012	0.818
2013	0.818
2014	0.818
2015	0.818
2016	0.818
2017	0.818
2018	0.818
2019	0.818
2020	0.818