Year	Tonnes
1942	0
1943	7.334
1944	3.667
1945	7.334
1946	3.667
1947	7.334
1948	7.334
1949	7.334
1950	190.684
1951	201.685
1952	275.025
1953	286.026
1954	315.362
1955	392.369
1956	377.701
1957	418.038
1958	601.388
1959	480.377
1960	531.715
1961	561.051
1962	660.06
1963	843.41
1964	949.753
1965	781.071
1966	960.754
1967	1081.765
1968	1232.112
1969	1287.117
1970	1404.461
1971	1507.137
1972	1606.146
1973	1829.833
1974	1950.844
1975	1928.842
1976	2225.869
1977	2838.258
1978	2632.906
1979	1712.489
1980	2027.851
1981	2141.528
1982	2115.859
1983	2002.182
1984	1851.835
1985	1991.181
1986	2262.539
1987	2438.555
1988	2247.871
1989	1477.801
1990	2548.565
1991	2005.849
1992	2394.551
1993	2302.876
1994	2541.231
1995	2779.586
1996	2874.928
1997	3142.619
1998	3421.311
1999	3626.663
2000	3762.342
2001	3964.027
2002	4037.367
2003	4411.401
2004	4426.069
2005	4319.726
2006	4466.406
2007	4605.752
2008	4422.402
2009	4495.742
2010	4536.079
2011	4880.777
2012	4620.42
2013	4550.747
2014	4862.442