Year	billion cubic meters
1990	0.0017
1991	0.0019266667
1992	0.0021533333
1993	0.00238
1994	0.0026066667
1995	0.0028333333
1996	0.00306
1997	0.0032866667
1998	0.0035133333
1999	0.00374
2000	0.0039666667
2001	0.0041933333
2002	0.00442
2003	0.0046466667
2004	0.0048733333
2005	0.0051
2006	0.005
2007	0.0049
2008	0.0048
2009	0.0047
2010	0.0046
2011	0.0045
2012	0.0044
2013	0.0044
2014	0.0044
2015	0.0044
2016	0.0044
2017	0.0044
2018	0.0044
2019	0.0044
2020	0.0044