Year	Tonnes
1962	3.667
1963	3.667
1964	7.334
1965	3.667
1966	7.334
1967	7.334
1968	7.334
1969	7.334
1970	14.668
1971	14.668
1972	14.668
1973	14.668
1974	14.668
1975	11.001
1976	11.001
1977	25.669
1978	25.669
1979	25.669
1980	14.668
1981	18.335
1982	18.335
1983	22.002
1984	22.002
1985	25.669
1986	29.336
1987	29.336
1988	29.336
1989	29.336
1990	29.336
1991	29.336
1992	29.336
1993	29.336
1994	33.003
1995	33.003
1996	36.67
1997	33.003
1998	29.336
1999	29.336
2000	25.669
2001	25.669
2002	36.67
2003	36.67
2004	36.67
2005	36.67
2006	36.67
2007	40.337
2008	47.671
2009	47.671
2010	66.006
2011	40.337
2012	44.004
2013	51.338
2014	47.671