Year	kt
1990	62.7
1991	62.7
1992	62.8
1993	66.1
1994	69.4
1995	83.1
1996	69.7
1997	91.1
1998	92.9
1999	102.3
2000	125.3
2001	139.1
2002	105.6
2003	121.5
2004	144.3
2005	148.4
2006	155.3
2007	164
2008	165.7
2009	163.8
2010	172.5
2011	152.1
2012	167
2013	171.4
2014	180
2015	180.9
2016	182.5
2017	165.6
2018	165.3
2019	174.1
2020	162.8