Year	kt
1960	517.047
1961	542.716
1962	638.058
1963	817.741
1964	920.417
1965	748.068
1966	920.417
1967	1034.094
1968	1180.774
1969	1232.112
1970	1342.122
1971	1448.465
1972	1547.474
1973	1734.491
1974	1833.5
1975	1840.834
1976	2112.192
1977	2724.581
1978	2533.897
1979	1668.485
1980	1950.844
1981	2057.187
1982	2064.521
1983	1950.844
1984	1800.497
1985	1939.843
1986	2211.201
1987	2387.217
1988	2196.533
1989	1411.795
1990	1950.844
1991	1884.838
1992	2255.205
1993	2174.531
1994	2387.217
1995	2618.238
1996	2695.245
1997	2955.602
1998	3234.294
1999	3450.647
2000	3498.318
2001	3707.337
2002	3762.342
2003	3967.694
2004	4165.712
2005	4055.702
2006	4206.049
2007	4341.728
2008	4158.378
2009	4239.052
2010	4235.385
2011	4536.079
2012	4308.725
2013	4103.373
2014	4330.727
2015	4983.453
2016	5243.81