Year	kt
1960	10124.587
1961	9394.854
1962	8683.456
1963	8808.134
1964	8760.463
1965	7873.049
1966	7572.355
1967	7546.686
1968	6622.602
1969	6475.922
1970	6992.969
1971	6321.908
1972	5427.16
1973	5808.528
1974	5786.526
1975	7091.978
1976	6582.265
1977	5379.489
1978	5672.849
1979	6882.959
1980	6413.583
1981	5467.497
1982	6736.279
1983	7854.714
1984	9746.886
1985	11752.735
1986	11778.404
1987	11195.351
1988	11067.006
1989	10802.982
1990	11015.668
1991	10293.269
1992	9757.887
1993	10403.279
1994	11294.36
1995	10971.664
1996	11554.717
1997	9963.239
1998	9699.215
1999	9240.84
2000	9295.845
2001	10527.957
2002	10861.654
2003	10164.924
2004	11272.358
2005	9900.9
2006	10157.59
2007	10098.918
2008	9277.51
2009	7370.67
2010	9519.532
2011	9493.863
2012	8305.755
2013	8426.766
2014	8005.061
2015	8045.398
2016	7854.714