Year	Tonnes
1950	139.346
1951	183.35
1952	282.359
1953	201.685
1954	231.021
1955	234.688
1956	238.355
1957	256.69
1958	278.692
1959	278.692
1960	271.358
1961	282.359
1962	289.693
1963	300.694
1964	337.364
1965	311.695
1966	344.698
1967	458.375
1968	506.046
1969	572.052
1970	638.058
1971	810.407
1972	861.745
1973	898.415
1974	975.422
1975	1162.439
1976	1092.766
1977	1565.809
1978	2002.182
1979	1829.833
1980	3905.355
1981	5342.819
1982	6343.91
1983	6589.599
1984	6057.884
1985	6475.922
1986	1994.848
1987	1844.501
1988	2200.2
1989	7634.694
1990	1734.491
1991	1103.767
1992	3788.011
1993	3898.021
1994	3817.347
1995	4228.051
1996	4462.739
1997	3215.959
1998	3208.625
1999	3080.28
2000	3432.312
2001	3421.311
2002	3417.644
2003	3795.345
2004	3956.693
2005	3696.336
2006	3861.351
2007	5834.197
2008	5544.504
2009	6725.278
2010	6780.283
2011	5768.191
2012	6127.557
2013	6772.949
2014	7003.97