Year	kt
1960	1019.426
1961	2959.269
1962	5526.169
1963	-370.367
1964	1617.147
1965	2849.259
1966	1301.785
1967	1624.481
1968	872.746
1969	707.731
1970	3355.305
1971	2698.912
1972	2959.269
1973	3483.65
1974	3278.298
1975	2731.915
1976	8166.409
1977	7697.033
1978	6376.913
1979	7102.979
1980	5757.19
1981	6640.937
1982	5148.468
1983	1965.512
1984	2896.93
1985	3410.31
1986	2786.92
1987	2728.248
1988	2915.265
1989	2225.869
1990	3556.99
1991	3197.624
1992	4858.775
1993	4121.708
1994	3274.631
1995	3267.297
1996	4316.059
1997	2284.541
1998	2541.231
1999	3916.356
2000	3854.017
2001	3443.313
2002	3567.991
2003	4129.042
2004	3333.303
2005	4140.043
2006	4151.044
2007	5082.462
2008	5177.804
2009	5346.486
2010	5496.833
2011	5038.458
2012	4481.074
2013	5034.791
2014	4554.414
2015	5027.457
2016	5705.852