Year	Tonnes
1931	3.667
1932	11.001
1933	14.668
1935	51.338
1936	58.672
1937	62.339
1938	62.339
1939	58.672
1940	22.002
1941	22.002
1942	352.032
1943	36.67
1944	66.006
1945	73.34
1946	73.34
1947	84.341
1948	102.676
1949	117.344
1950	1514.471
1951	1459.466
1952	1177.107
1953	1250.447
1954	1309.119
1955	1624.481
1956	1888.505
1957	2068.188
1958	1983.847
1959	2453.223
1960	2581.568
1961	2684.244
1962	2856.593
1963	3028.942
1964	3267.297
1965	3318.635
1966	3630.33
1967	3571.658
1968	3700.003
1969	4352.729
1970	3949.359
1971	5339.152
1972	5727.854
1973	7172.652
1974	7231.324
1975	6431.918
1976	6127.557
1977	5573.84
1978	5713.186
1979	6156.893
1980	6178.895
1981	6351.244
1982	6112.889
1983	7319.332
1984	7051.641
1985	8056.399
1986	7759.372
1987	7968.391
1988	7660.363
1989	8052.732
1990	8214.08
1991	8478.104
1992	10359.275
1993	11683.062
1994	12702.488
1995	13578.901
1996	13758.584
1997	15647.089
1998	16648.18
1999	16490.499
2000	15247.386
2001	16171.47
2002	16002.788
2003	18180.986
2004	16798.527
2005	16208.14
2006	14458.981
2007	13461.557
2008	17227.566
2009	20872.564
2010	20047.489
2011	20443.525
2012	22632.724
2013	22581.386
2014	24070.188