Year	Tonnes
1928	3.667
1929	11.001
1930	11.001
1931	7.334
1932	14.668
1933	44.004
1934	73.34
1935	69.673
1936	44.004
1937	55.005
1938	66.006
1939	84.341
1940	128.345
1941	106.343
1942	135.679
1943	146.68
1944	139.346
1945	168.682
1946	161.348
1947	168.682
1948	205.352
1949	289.693
1950	495.045
1951	462.042
1952	513.38
1953	539.049
1954	788.405
1955	931.418
1956	1107.434
1957	1004.758
1958	916.75
1959	949.753
1960	1004.758
1961	1041.428
1962	1100.1
1963	1213.777
1964	1481.468
1965	1510.804
1966	1690.487
1967	1892.172
1968	2178.198
1969	2548.565
1970	2486.226
1971	3061.945
1972	3571.658
1973	3457.981
1974	3516.653
1975	4059.369
1976	4580.083
1977	4481.074
1978	5027.457
1979	4737.764
1980	4668.091
1981	4792.769
1982	4349.062
1983	4290.39
1984	4041.034
1985	4125.375
1986	3777.01
1987	4030.033
1988	4308.725
1989	4994.454
1990	5757.19
1991	6006.546
1992	6655.605
1993	7829.045
1994	8635.785
1995	9849.562
1996	9827.56
1997	10942.328
1998	10989.999
1999	10443.616
2000	11067.006
2001	8621.117
2002	10395.945
2003	11092.675
2004	11114.677
2005	12185.441
2006	15056.702
2007	12332.121
2008	13237.87
2009	13989.605
2010	15203.382
2011	16145.801
2012	18793.375
2013	18918.053
2014	20410.522