Year	billion cubic meters
1961	6463.4490000000005
1962	6602.864
1963	6602.8640000000005
1964	6602.8640000000005
1965	6602.864
1966	6602.8640000000005
1967	6602.8640000000005
1968	6602.8640000000005
1969	6602.8640000000005
1970	6602.8640000000005
1971	6602.864
1972	6602.8640000000005
1973	6602.8640000000005
1974	6602.864
1975	6602.864000000001
1976	6602.863999999999
1977	6602.863999999999
1978	6602.8640000000005
1979	6602.8640000000005
1980	6602.8640000000005
1981	6602.8640000000005
1982	6602.8640000000005
1983	6602.8640000000005
1984	6602.863999999999
1985	6602.8640000000005
1986	6602.8640000000005
1987	6602.864000000001
1988	6602.864000000001
1989	6602.8640000000005
1990	6602.8640000000005
1991	6602.864000000001
1992	6731.594000000001
1993	6856.394000000001
1994	6842.394000000001
1995	6842.394000000001
1996	6842.394000000001
1997	6842.394000000001
1998	6842.394000000001
1999	6842.394
2000	6842.394000000001
2001	6842.394000000001
2002	6842.393999999999
2003	6842.394000000001
2004	6839.394000000001
2005	6839.394000000001
2006	6839.394000000001
2007	6839.393999999999
2008	6839.394000000001
2009	6839.394000000001
2010	6839.394000000001
2011	6839.393999999999
2012	6869.394000000001
2013	6869.394000000001
2014	6869.394000000001
2015	6869.394000000001
2016	6869.394000000001
2017	6869.394000000001
2018	6869.394000000001
2019	6869.394000000001
2020	6869.394000000001