Year	Tonnes
1959	22.002
1960	132.012
1961	165.015
1962	88.008
1963	73.34
1964	190.684
1965	216.353
1966	381.368
1967	1012.092
1968	1961.845
1969	1433.797
1970	2082.856
1971	2845.592
1972	2739.249
1973	5313.483
1974	5452.829
1975	5368.488
1976	5709.519
1977	6314.574
1978	7561.354
1979	6754.614
1980	6633.603
1981	6574.931
1982	6556.596
1983	5518.835
1984	5995.545
1985	6318.241
1986	4968.785
1987	4022.699
1988	4334.394
1989	5771.858
1990	4499.409
1991	4536.079
1992	4932.115
1993	4990.787
1994	4389.399
1995	4624.087
1996	4774.434
1997	4796.436
1998	4979.786
1999	4807.437
2000	4693.76
2001	4800.103
2002	4572.749
2003	4642.422
2004	4686.426
2005	4888.111
2006	4173.046
2007	4118.041
2008	4173.046
2009	4250.053
2010	4811.104
2011	4972.452
2012	5104.464
2013	5280.48
2014	5192.472