Year	billion cubic meters
1961	3877.097
1962	3924.2470000000003
1963	3924.2470000000003
1964	3924.2470000000003
1965	3924.2470000000003
1966	3924.2470000000008
1967	3924.2470000000008
1968	3924.2470000000008
1969	3924.2470000000008
1970	3924.2470000000008
1971	3924.2470000000008
1972	3924.2470000000003
1973	3924.2470000000003
1974	3924.2470000000008
1975	3924.2470000000008
1976	3924.2470000000008
1977	3924.2470000000008
1978	3924.2470000000003
1979	3924.2470000000003
1980	3924.2470000000003
1981	3924.2470000000008
1982	3924.2470000000008
1983	3924.2470000000008
1984	3924.2470000000008
1985	3924.2470000000003
1986	3924.2470000000003
1987	3924.2470000000003
1988	3924.2470000000008
1989	3924.2470000000008
1990	3924.2470000000008
1991	3924.2470000000008
1992	3924.2470000000008
1993	4049.0470000000005
1994	4049.0470000000005
1995	4049.0470000000005
1996	4049.0470000000005
1997	4049.0470000000005
1998	4049.047
1999	4049.0470000000005
2000	4049.0470000000005
2001	4049.0470000000005
2002	4049.047
2003	4049.0470000000005
2004	4049.0470000000005
2005	4049.0470000000005
2006	4049.0470000000005
2007	4049.0470000000005
2008	4049.0470000000005
2009	4049.0470000000005
2010	4049.0470000000005
2011	4049.0470000000005
2012	4053.0470000000005
2013	4053.0470000000005
2014	4053.0470000000005
2015	4053.0470000000005
2016	4053.0470000000005
2017	4053.0470000000005
2018	4053.0470000000005
2019	4053.0470000000005
2020	4053.0470000000005