Year	billion cubic meters
1961	2.64
1962	2.64
1963	2.64
1964	2.64
1965	2.64
1966	2.64
1967	2.64
1968	2.64
1969	2.64
1970	2.64
1971	2.64
1972	2.64
1973	2.64
1974	2.64
1975	2.64
1976	2.64
1977	2.64
1978	2.64
1979	2.64
1980	2.64
1981	2.64
1982	2.64
1983	2.64
1984	2.64
1985	2.64
1986	2.64
1987	2.64
1988	2.64
1989	2.64
1990	2.64
1991	2.64
1992	2.64
1993	2.64
1994	2.64
1995	2.64
1996	2.64
1997	2.64
1998	2.64
1999	2.64
2000	2.64
2001	2.64
2002	2.64
2003	2.64
2004	2.64
2005	2.64
2006	2.64
2007	2.64
2008	2.64
2009	2.64
2010	2.64
2011	2.64
2012	2.64
2013	2.64
2014	2.64
2015	2.64
2016	2.64
2017	2.64
2018	2.64
2019	2.64
2020	2.64