Year	Tonnes
1931	29.336
1932	25.669
1933	22.002
1934	25.669
1935	25.669
1936	29.336
1937	36.67
1938	40.337
1939	47.671
1940	58.672
1941	58.672
1943	33.003
1944	14.668
1947	29.336
1948	40.337
1949	62.339
1950	957.087
1951	1092.766
1952	1279.783
1953	1646.483
1954	2053.52
1955	2376.216
1956	2621.905
1957	2926.266
1958	3021.608
1959	3325.969
1960	3714.671
1961	4147.377
1962	5034.791
1963	5570.173
1964	7480.68
1965	7451.344
1966	9479.195
1967	12167.106
1968	17099.221
1969	14561.657
1970	15375.731
1971	19248.083
1972	21836.985
1973	24455.223
1974	24246.204
1975	24407.552
1976	28778.616
1977	32159.59
1978	35067.521
1979	36736.006
1980	40135.315
1981	38048.792
1982	37909.446
1983	42452.859
1984	45973.179
1985	48672.091
1986	49702.518
1987	56944.843
1988	67003.424
1989	78891.838
1990	90805.921
1991	99782.737
1992	109778.979
1993	124949.358
1994	139158.983
1995	161153.649
1996	180255.052
1997	185916.9
1998	164347.606
1999	176126.01
2000	181270.811
2001	194600.356
2002	208322.27
2003	224574.414
2004	243188.106
2005	247467.495
2006	252047.578
2007	252447.281
2008	252443.614
2009	267602.992
2010	281926.294
2011	278317.966
2012	296597.961
2013	300088.945
2014	316212.744