Year	kt
1960	297.027
1961	355.699
1962	385.035
1963	403.37
1964	421.705
1965	535.382
1966	498.712
1967	480.377
1968	579.386
1969	502.379
1970	700.397
1971	605.055
1972	678.395
1973	832.409
1974	902.082
1975	770.07
1976	957.087
1977	1059.763
1978	1375.125
1979	1254.114
1980	1404.461
1981	1312.786
1982	1312.786
1983	1338.455
1984	1441.131
1985	1529.139
1986	1576.81
1987	1760.16
1988	2002.182
1989	2082.856
1990	1994.848
1991	1969.179
1992	2361.548
1993	2706.246
1994	3142.619
1995	3648.665
1996	3446.98
1997	3857.684
1998	4140.043
1999	4140.043
2000	3366.306
2001	3498.318
2002	3674.334
2003	3810.013
2004	3854.017
2005	3556.99
2006	3685.335
2007	3835.682
2008	4052.035
2009	4261.054
2010	4774.434
2011	4994.454
2012	4877.11
2013	4954.117
2014	5203.473
2015	5694.851
2016	6802.285