Year	Tonnes
1950	7.334
1951	11.001
1952	11.001
1953	11.001
1954	11.001
1955	11.001
1956	11.001
1957	11.001
1958	14.668
1959	14.668
1960	22.002
1961	18.335
1962	25.669
1963	14.668
1964	22.002
1965	22.002
1966	29.336
1967	36.67
1968	40.337
1969	47.671
1970	44.004
1971	47.671
1972	47.671
1973	55.005
1974	36.67
1975	47.671
1976	47.671
1977	47.671
1978	51.338
1979	47.671
1980	47.671
1981	58.672
1982	62.339
1983	62.339
1984	62.339
1985	62.339
1986	66.006
1987	73.34
1988	95.342
1989	102.676
1990	106.343
1991	110.01
1992	117.344
1993	121.011
1994	143.013
1995	150.347
1996	154.014
1997	168.682
1998	176.016
1999	194.351
2000	190.684
2001	194.351
2002	205.352
2003	216.353
2004	205.352
2005	216.353
2006	231.021
2007	238.355
2008	253.023
2009	253.023
2010	260.357
2011	253.023
2012	271.358
2013	304.361
2014	242.022