Year	Tonnes
1950	102.676
1951	77.007
1952	36.67
1953	18.335
1954	22.002
1955	22.002
1956	29.336
1957	18.335
1958	14.668
1959	18.335
1960	22.002
1961	22.002
1962	18.335
1963	14.668
1964	29.336
1965	25.669
1966	22.002
1967	18.335
1968	29.336
1969	36.67
1970	36.67
1971	36.67
1972	51.338
1973	62.339
1974	66.006
1975	77.007
1976	73.34
1977	80.674
1978	209.019
1979	249.356
1980	121.011
1981	33.003
1982	36.67
1983	36.67
1984	84.341
1985	84.341
1986	58.672
1987	80.674
1988	73.34
1989	80.674
1990	95.342
1991	99.009
1992	106.343
1993	110.01
1994	113.677
1995	121.011
1996	143.013
1997	146.68
1998	157.681
1999	183.35
2000	216.353
2001	234.688
2002	275.025
2003	308.028
2004	330.03
2005	440.04
2006	473.043
2007	506.046
2008	469.376
2009	524.381
2010	557.384
2011	616.056
2012	506.046
2013	498.712
2014	491.378