Year	kt
1960	5984.544
1961	6967.3
1962	8547.777
1963	9402.188
1964	11235.688
1965	13516.562
1966	14781.677
1967	16138.467
1968	19468.103
1969	20689.214
1970	25742.34
1971	27344.819
1972	30062.066
1973	34645.816
1974	36677.334
1975	41499.439
1976	45452.465
1977	49625.511
1978	52702.124
1979	55877.746
1980	56295.784
1981	48763.766
1982	46435.221
1983	44906.082
1984	40340.667
1985	41191.411
1986	42603.206
1987	42133.83
1988	39728.278
1989	39486.256
1990	34154.438
1991	34422.129
1992	36446.313
1993	37502.409
1994	39739.279
1995	42386.853
1996	46600.236
1997	47766.342
1998	48947.116
1999	50549.595
2000	49768.524
2001	52551.777
2002	52126.405
2003	52933.145
2004	56735.824
2005	57018.183
2006	59772.1
2007	61242.567
2008	64033.154
2009	62412.34
2010	65646.634
2011	66468.042
2012	63714.125
2013	57010.849
2014	56068.43
2015	58660.999
2016	66251.689