Year	Tonnes
1950	187.017
1951	249.356
1952	311.695
1953	275.025
1954	348.365
1955	414.371
1956	502.379
1957	619.723
1958	594.054
1959	619.723
1960	550.05
1961	454.708
1962	1180.774
1963	1151.438
1964	1224.778
1965	1188.108
1966	1554.808
1967	993.757
1968	1672.152
1969	2786.92
1970	3582.659
1971	3410.31
1972	4506.743
1973	4880.777
1974	4873.443
1975	4415.068
1976	3285.632
1977	3534.988
1978	5412.492
1979	5504.167
1980	5346.486
1981	5280.48
1982	4649.756
1983	5115.465
1984	5009.122
1985	4701.094
1986	4660.757
1987	5815.862
1988	5130.133
1989	5009.122
1990	5115.465
1991	5089.796
1992	5196.139
1993	5775.525
1994	3890.687
1995	10975.331
1996	10458.284
1997	7381.671
1998	7308.331
1999	9156.499
2000	9541.534
2001	9732.218
2002	12665.818
2003	9064.824
2004	18793.375
2005	19156.408
2006	22266.024
2007	25151.953
2008	25709.337
2009	27792.193
2010	29057.308
2011	30340.758
2012	33399.036
2013	32617.965
2014	34763.16