Year	kt
1960	31822.226
1961	33604.388
1962	34543.14
1963	34506.47
1964	32570.294
1965	34499.136
1966	31946.904
1967	32166.924
1968	32760.978
1969	32823.317
1970	36409.643
1971	35159.196
1972	36215.292
1973	35148.195
1974	36780.01
1975	41173.076
1976	40648.695
1977	44392.702
1978	36259.296
1979	42188.835
1980	49291.814
1981	56809.164
1982	66350.698
1983	69405.309
1984	69573.991
1985	75067.157
1986	73501.348
1987	70377.064
1988	61040.882
1989	75485.195
1990	73556.353
1991	76258.932
1992	78169.439
1993	70241.385
1994	72027.214
1995	72456.253
1996	61748.613
1997	69676.667
1998	67175.773
1999	75107.494
2000	79680.243
2001	72987.968
2002	82393.823
2003	76280.934
2004	79735.248
2005	78103.433
2006	70054.368
2007	75536.533
2008	53791.223
2009	40135.315
2010	31033.821
2011	47384.974
2012	58290.632
2013	41638.785
2014	43461.284
2015	50237.9
2016	38928.872