Year	Tonnes
1963	7334
1964	14668
1965	22002
1966	29336
1967	36670
1968	44004
1969	51338
1970	80674
1971	113677
1972	157681
1973	205352
1974	260357
1975	319029
1976	399703
1977	484044
1978	561051
1979	682062
1980	777404
1981	876413
1982	960754
1983	1059763
1984	1158772
1985	1309119
1986	1474134
1987	1675819
1988	1873837
1989	2108525
1990	2258872
1991	2431221
1992	2603570
1993	2786920
1994	2988605
1995	3186623
1996	3421311
1997	3762342
1998	4195048
1999	4704761
2000	5276813
2001	5911204
2002	6450253
2003	7000303
2004	7737370
2005	8426766
2006	9160166
2007	9801891
2008	10494954
2009	11019335
2010	11463042
2011	11804073
2012	12244113
2013	12647483
2014	13142528
