Year	Tonnes
1950	18.335
1951	25.669
1952	25.669
1953	29.336
1954	29.336
1955	29.336
1956	29.336
1957	29.336
1958	40.337
1959	40.337
1960	44.004
1961	36.67
1962	69.673
1963	62.339
1964	84.341
1965	84.341
1966	80.674
1967	121.011
1968	102.676
1969	135.679
1970	121.011
1971	143.013
1972	157.681
1973	146.68
1974	154.014
1975	176.016
1976	176.016
1977	198.018
1978	216.353
1979	209.019
1980	190.684
1981	183.35
1982	172.349
1983	172.349
1984	172.349
1985	190.684
1986	205.352
1987	227.354
1988	249.356
1989	300.694
1990	311.695
1991	359.366
1992	355.699
1993	377.701
1994	374.034
1995	377.701
1996	308.028
1997	388.702
1998	370.367
1999	348.365
2000	396.036
2001	447.374
2002	432.706
2003	432.706
2004	392.369
2005	421.705
2006	443.707
2007	476.71
2008	436.373
2009	586.72
2010	539.049
2011	601.388
2012	476.71
2013	513.38
2014	495.045