Year	kt
1960	16706.852
1961	16600.509
1962	18081.977
1963	19380.095
1964	18591.69
1965	20205.17
1966	20931.236
1967	22878.413
1968	24818.256
1969	27894.869
1970	34037.094
1971	35943.934
1972	37788.435
1973	42482.195
1974	39471.588
1975	42478.528
1976	47982.695
1977	52566.445
1978	59695.093
1979	60208.473
1980	58393.308
1981	51264.66
1982	50538.594
1983	46493.893
1984	46699.245
1985	48793.102
1986	53545.534
1987	61462.587
1988	56248.113
1989	57256.538
1990	55437.706
1991	44033.336
1992	35060.187
1993	38818.862
1994	35228.869
1995	39944.631
1996	39511.925
1997	38400.824
1998	33945.419
1999	28415.583
2000	27161.469
2001	31979.907
2002	30414.098
2003	29842.046
2004	27176.137
2005	26270.388
2006	28646.604
2007	28279.904
2008	26530.745
2009	23758.493
2010	23795.163
2011	23564.142
2012	23083.765
2013	22134.012
2014	21814.983
2015	23765.827
2016	23846.501