Year	Tonnes
1964	330.03
1965	348.365
1966	429.039
1967	366.7
1968	388.702
1969	381.368
1970	454.708
1971	502.379
1972	546.383
1973	572.052
1974	550.05
1975	579.386
1976	583.053
1977	638.058
1978	671.061
1979	638.058
1980	711.398
1981	605.055
1982	594.054
1983	575.719
1984	557.384
1985	557.384
1986	553.717
1987	546.383
1988	542.716
1989	564.718
1990	748.068
1991	795.739
1992	795.739
1993	891.081
1994	916.75
1995	920.417
1996	913.083
1997	964.421
1998	935.085
1999	942.419
2000	869.079
2001	865.412
2002	850.744
2003	916.75
2004	931.418
2005	876.413
2006	913.083
2007	887.414
2008	1056.096
2009	946.086
2010	1144.104
2011	1180.774
2012	1096.433
2013	1224.778
2014	1276.116