Year	kt
1960	0
1961	0
1962	0
1963	0
1964	0
1965	0
1966	0
1967	0
1968	0
1969	0
1970	0
1971	0
1972	0
1973	0
1974	29.336
1975	399.703
1976	667.394
1977	938.752
1978	3879.686
1979	1620.814
1980	3193.957
1981	7311.998
1982	7792.375
1983	5911.204
1984	7755.705
1985	7836.379
1986	12959.178
1987	5676.516
1988	9636.876
1989	11701.397
1990	4525.078
1991	4426.069
1992	7414.674
1993	8463.436
1994	8995.151
1995	7928.054
1996	6835.288
1997	8980.483
1998	9864.23
1999	10894.657
2000	9493.863
2001	14110.616
2002	9827.56
2003	11888.414
2004	9259.175
2005	9325.181
2006	9215.171
2007	11147.68
2008	16464.83
2009	15958.784
2010	14385.641
2011	11771.07
2012	12453.132
2013	12944.51
2014	13234.203
2015	13985.938
2016	12680.486