Year	kt
1960	8423.099
1961	9559.869
1962	11034.003
1963	12346.789
1964	14583.659
1965	14767.009
1966	16479.498
1967	18415.674
1968	20931.236
1969	22401.703
1970	24799.921
1971	27795.86
1972	30293.087
1973	33549.383
1974	29361.669
1975	28892.293
1976	31928.569
1977	31433.524
1978	31891.899
1979	34579.81
1980	26094.372
1981	30014.395
1982	28675.94
1983	26439.07
1984	25514.986
1985	25346.304
1986	27810.528
1987	31037.488
1988	27429.16
1989	27836.197
1990	27645.513
1991	30098.736
1992	29060.975
1993	30183.077
1994	29644.028
1995	30040.064
1996	32430.948
1997	31642.543
1998	33989.423
1999	32005.576
2000	31400.521
2001	33663.06
2002	34587.144
2003	37102.706
2004	37132.042
2005	37729.763
2006	36600.327
2007	35793.587
2008	34535.806
2009	32617.965
2010	33795.072
2011	32042.246
2012	31008.152
2013	31646.21
2014	30480.104
2015	30905.476
2016	31312.513