Year	Tonnes
1959	187.017
1960	223.687
1961	267.691
1962	238.355
1963	234.688
1964	267.691
1965	245.689
1966	308.028
1967	322.696
1968	451.041
1969	502.379
1970	572.052
1971	685.729
1972	663.727
1973	1221.111
1974	1624.481
1975	1100.1
1976	1235.779
1977	480.377
1978	322.696
1979	348.365
1980	407.037
1981	473.043
1982	1345.789
1983	1144.104
1984	1140.437
1985	1279.783
1986	1067.097
1987	1323.787
1988	1499.803
1989	1507.137
1990	1188.108
1991	1004.758
1992	1279.783
1993	1320.12
1994	2148.862
1995	1565.809
1996	1716.156
1997	2343.213
1998	777.404
1999	821.408
2000	1048.762
2001	766.403
2002	575.719
2003	916.75
2004	949.753
2005	982.756
2006	1118.435
2007	1213.777
2008	1309.119
2009	1745.492
2010	1980.18
2011	2258.872
2012	2970.27
2013	3087.614
2014	3094.948