Year	billion cubic meters
1961	4351.217000000001
1962	4451.282
1963	4451.282
1964	4451.282
1965	4451.282
1966	4451.282
1967	4451.282
1968	4451.282
1969	4451.282
1970	4451.282
1971	4451.282000000001
1972	4451.282
1973	4451.282
1974	4451.282000000001
1975	4451.282000000001
1976	4451.282000000001
1977	4451.282000000001
1978	4451.282
1979	4451.282
1980	4451.282
1981	4451.282000000001
1982	4451.282000000001
1983	4451.282
1984	4451.282
1985	4451.282
1986	4451.282
1987	4451.282000000001
1988	4451.282000000001
1989	4451.282
1990	4451.282
1991	4451.282000000001
1992	4451.282
1993	4576.082
1994	4562.082
1995	4562.082
1996	4562.082
1997	4562.082
1998	4562.082
1999	4562.082
2000	4562.082
2001	4562.082
2002	4562.082
2003	4562.082
2004	4559.082
2005	4559.082000000001
2006	4559.082000000001
2007	4559.082
2008	4559.082
2009	4559.082
2010	4559.082
2011	4559.082
2012	4589.082000000001
2013	4589.082
2014	4589.082
2015	4589.082
2016	4589.082000000001
2017	4589.082000000001
2018	4589.082
2019	4589.082
2020	4589.082000000001
