Year	billion cubic meters
1961	25.8
1962	25.8
1963	25.8
1964	25.8
1965	25.8
1966	25.8
1967	25.8
1968	25.8
1969	25.8
1970	25.8
1971	25.8
1972	25.8
1973	25.8
1974	25.8
1975	25.8
1976	25.8
1977	25.8
1978	25.8
1979	25.8
1980	25.8
1981	25.8
1982	25.8
1983	25.8
1984	25.8
1985	25.8
1986	25.8
1987	25.8
1988	25.8
1989	25.8
1990	25.8
1991	25.8
1992	25.8
1993	25.8
1994	25.8
1995	25.8
1996	25.8
1997	25.8
1998	25.8
1999	25.8
2000	25.8
2001	25.8
2002	25.8
2003	25.8
2004	25.8
2005	25.8
2006	25.8
2007	25.8
2008	25.8
2009	25.8
2010	25.8
2011	25.8
2012	25.8
2013	25.8
2014	25.8
2015	25.8
2016	25.8
2017	25.8
2018	25.8
2019	25.8
2020	25.8