Year	Tonnes
1964	11.001
1965	25.669
1966	29.336
1967	135.679
1968	161.348
1969	234.688
1970	234.688
1971	2093.857
1972	2090.19
1973	2112.192
1974	2335.879
1975	7256.993
1976	8327.757
1977	8507.44
1978	7796.042
1979	7722.702
1980	6046.883
1981	6017.547
1982	5735.188
1983	7532.018
1984	8060.066
1985	8661.454
1986	9875.231
1987	9464.527
1988	10586.629
1989	10065.915
1990	11386.035
1991	11771.07
1992	12079.098
1993	13457.89
1994	15306.058
1995	15896.445
1996	15104.373
1997	15485.741
1998	16560.172
1999	20707.549
2000	21895.657
2001	20285.844
2002	25470.982
2003	32390.611
2004	27986.544
2005	29893.384
2006	39603.6
2007	43695.972
2008	42705.882
2009	41103.403
2010	47417.977
2011	54029.578
2012	59159.711
2013	61378.246
2014	61169.227