Year	Tonnes
1958	355.699
1959	388.702
1960	828.742
1961	814.074
1962	814.074
1963	861.745
1964	924.084
1965	1694.154
1966	1719.823
1967	700.397
1968	0
1969	491.378
1970	1309.119
1971	1353.123
1972	1455.799
1973	1551.141
1974	1851.835
1975	2581.568
1976	1774.828
1977	2244.204
1978	2629.239
1979	2900.597
1980	3351.638
1981	3296.633
1982	3054.611
1983	2632.906
1984	3307.634
1985	2676.91
1986	2662.242
1987	2453.223
1988	2742.916
1989	3696.336
1990	3182.956
1991	3424.978
1992	3479.983
1993	3593.66
1994	3901.688
1995	3494.651
1996	3740.34
1997	3263.63
1998	3428.645
1999	3700.003
2000	3938.358
2001	4330.727
2002	4510.41
2003	4976.119
2004	5232.809
2005	5812.195
2006	4730.43
2007	5181.471
2008	5093.463
2009	4583.75
2010	7744.704
2011	8368.094
2012	7913.386
2013	8423.099
2014	8855.805