Year	billion cubic meters
1961	15517.076000000001
1962	15561.686000000002
1963	15561.686000000002
1964	15561.686000000002
1965	15561.686000000002
1966	15561.686000000002
1967	15561.686000000002
1968	15561.686000000002
1969	15561.686000000002
1970	15561.686000000002
1971	15561.686000000002
1972	15561.686000000002
1973	15561.686000000002
1974	15561.686000000002
1975	15561.686000000002
1976	15561.686000000002
1977	15561.686000000002
1978	15561.686000000002
1979	15561.686000000002
1980	15561.686000000002
1981	15561.686000000002
1982	15561.686000000002
1983	15561.686000000002
1984	15561.686000000002
1985	15561.686000000002
1986	15561.686000000002
1987	15561.686000000002
1988	15561.686000000002
1989	15561.686000000002
1990	15561.686000000002
1991	15561.686000000002
1992	20089.065000000006
1993	20089.065000000006
1994	20089.065000000006
1995	20089.065000000006
1996	20088.165000000005
1997	20089.065000000006
1998	20089.065000000006
1999	20089.065000000006
2000	20089.065000000006
2001	20089.065000000006
2002	20089.065000000006
2003	20089.065000000006
2004	20089.065000000006
2005	20089.065000000006
2006	20097.472000000005
2007	20097.472000000005
2008	20097.472000000005
2009	20097.472000000005
2010	20097.472000000005
2011	20097.472000000005
2012	20097.472000000005
2013	20097.472000000005
2014	20097.472000000005
2015	20097.472000000005
2016	20097.472000000005
2017	20097.472000000005
2018	20097.472000000005
2019	20097.472000000005
2020	20097.472000000005