Year	kt
1960	2955.602
1961	3373.64
1962	3685.335
1963	4250.053
1964	4224.384
1965	4807.437
1966	5166.803
1967	6057.884
1968	6204.564
1969	7759.372
1970	8401.097
1971	9160.166
1972	9284.844
1973	9295.845
1974	10678.304
1975	11019.335
1976	12508.137
1977	14231.627
1978	15753.432
1979	15885.444
1980	16662.848
1981	18690.699
1982	19702.791
1983	21015.577
1984	22346.698
1985	23014.092
1986	25698.336
1987	28272.57
1988	29482.68
1989	30348.092
1990	27333.818
1991	28639.27
1992	33094.675
1993	34964.845
1994	31283.177
1995	31470.194
1996	29123.314
1997	30703.791
1998	39101.221
1999	42716.883
2000	40439.676
2001	37957.117
2002	39636.603
2003	43358.608
2004	41708.458
2005	43871.988
2006	42056.823
2007	43721.641
2008	43978.331
2009	42148.498
2010	40678.031
2011	43794.981
2012	43424.614
2013	45005.091
2014	46222.535