Year	kt
1972	0
1973	0
1974	0
1975	0
1976	0
1977	0
1978	0
1979	0
1980	0
1981	0
1982	0
1983	0
1984	0
1985	0
1986	0
1987	0
1988	0
1989	0
1990	953.42
1991	916.75
1992	836.076
1993	1272.449
1994	1078.098
1995	1070.764
1996	1169.773
1997	1100.1
1998	1320.12
1999	1565.809
2000	1727.157
2001	1844.501
2002	1888.505
2003	2024.184
2004	1914.174
2005	1954.511
2006	2046.186
2007	2295.542
2008	2552.232
2009	2181.865
2010	2445.889
2011	2592.569
2012	2746.583
2013	2885.929
2014	3003.273
2015	2519.229
2016	2757.584