Year	kt
1960	179.683
1961	201.685
1962	198.018
1963	256.69
1964	267.691
1965	304.361
1966	341.031
1967	436.373
1968	502.379
1969	557.384
1970	693.063
1971	825.075
1972	1268.782
1973	1345.789
1974	1587.811
1975	1532.806
1976	1573.143
1977	1580.477
1978	1675.819
1979	1796.83
1980	1829.833
1981	1932.509
1982	1947.177
1983	2009.516
1984	2046.186
1985	2123.193
1986	2060.854
1987	2332.212
1988	2196.533
1989	2031.518
1990	2005.849
1991	2020.517
1992	2042.519
1993	2038.852
1994	2013.183
1995	1866.503
1996	1917.841
1997	2346.88
1998	2596.236
1999	2211.201
2000	2420.22
2001	2911.598
2002	3190.29
2003	3670.667
2004	4235.385
2005	4088.705
2006	4030.033
2007	5859.866
2008	4503.076
2009	4792.769
2010	4374.731
2011	4928.448
2012	4719.429
2013	4895.445
2014	5471.164
2015	5555.505
2016	5823.196