Year	kt
1960	2460.557
1961	2830.924
1962	3168.288
1963	3780.677
1964	3784.344
1965	4352.729
1966	4759.766
1967	5720.52
1968	5848.865
1969	7469.679
1970	8126.072
1971	8822.802
1972	9028.154
1973	9053.823
1974	10359.275
1975	10703.973
1976	12082.765
1977	13685.244
1978	15108.04
1979	15218.05
1980	15903.779
1981	17817.953
1982	16079.795
1983	13468.891
1984	12365.124
1985	10879.989
1986	11602.388
1987	10898.324
1988	9581.871
1989	9134.497
1990	8309.422
1991	8254.417
1992	11551.05
1993	10102.585
1994	13171.864
1995	11976.422
1996	11221.02
1997	13234.203
1998	19398.43
1999	25232.627
2000	20736.885
2001	17469.588
2002	14781.677
2003	14763.342
2004	13780.586
2005	13663.242
2006	11837.076
2007	11741.734
2008	11719.732
2009	8870.473
2010	9446.192
2011	9244.507
2012	9607.54
2013	9435.191
2014	9273.843
2015	10219.929
2016	11063.339