Year	billion cubic meters
1961	1002.8
1962	1002.8
1963	1002.8
1964	1002.8
1965	1002.8
1966	1002.8
1967	1002.8
1968	1002.8
1969	1002.8
1970	1002.8
1971	1002.8
1972	1002.8
1973	1002.8
1974	1002.8
1975	1002.8
1976	1002.8
1977	1002.8
1978	1002.8
1979	1002.8
1980	1002.8
1981	1002.8
1982	1002.8
1983	1002.8
1984	1002.8
1985	1002.8
1986	1002.8
1987	1002.8
1988	1002.8
1989	1002.8
1990	1002.8
1991	1002.8
1992	1002.8
1993	1002.8
1994	1002.8
1995	1002.8
1996	1002.8
1997	1002.8
1998	1002.8
1999	1002.8
2000	1002.8
2001	1002.8
2002	1002.8
2003	1002.8
2004	1002.8
2005	1002.8
2006	1002.8
2007	1002.8
2008	1002.8
2009	1002.8
2010	1002.8
2011	1002.8
2012	1002.8
2013	1002.8
2014	1002.8
2015	1002.8
2016	1002.8
2017	1002.8
2018	1002.8
2019	1002.8
2020	1002.8