Year	kt
1960	1525.472
1961	1921.508
1962	2141.528
1963	2108.525
1964	1767.494
1965	2244.204
1966	2537.564
1967	2482.559
1968	3017.941
1969	4118.041
1970	3377.307
1971	2970.27
1972	3347.971
1973	3461.648
1974	2680.577
1975	2691.578
1976	2581.568
1977	2742.916
1978	3135.285
1979	3527.654
1980	3120.617
1981	3707.337
1982	4088.705
1983	4554.414
1984	3626.663
1985	3652.332
1986	3402.976
1987	3777.01
1988	3292.966
1989	3281.965
1990	3670.667
1991	3971.361
1992	4774.434
1993	4701.094
1994	5056.793
1995	5452.829
1996	6593.266
1997	7128.648
1998	7385.338
1999	8122.405
2000	9732.218
2001	9886.232
2002	10546.292
2003	10267.6
2004	11371.367
2005	11122.011
2006	10949.662
2007	11345.698
2008	11089.008
2009	12005.758
2010	12170.773
2011	13014.183
2012	13113.192
2013	11932.418
2014	13102.191
2015	13751.25
2016	16486.832