Year	Tonnes
1950	3.667
1951	3.667
1952	11.001
1953	7.334
1954	7.334
1955	7.334
1956	7.334
1957	7.334
1958	11.001
1959	11.001
1960	11.001
1961	11.001
1962	11.001
1963	14.668
1964	18.335
1965	14.668
1966	18.335
1967	18.335
1968	22.002
1969	29.336
1970	29.336
1971	29.336
1972	36.67
1973	40.337
1974	33.003
1975	33.003
1976	33.003
1977	33.003
1978	36.67
1979	29.336
1980	36.67
1981	36.67
1982	40.337
1983	47.671
1984	66.006
1985	66.006
1986	66.006
1987	77.007
1988	66.006
1989	77.007
1990	80.674
1991	77.007
1992	84.341
1993	102.676
1994	121.011
1995	128.345
1996	132.012
1997	132.012
1998	161.348
1999	165.015
2000	146.68
2001	179.683
2002	187.017
2003	198.018
2004	220.02
2005	220.02
2006	220.02
2007	227.354
2008	227.354
2009	311.695
2010	220.02
2011	198.018
2012	253.023
2013	209.019
2014	209.019