Year	kt
1990	14671.9
1991	15206.3
1992	16294.7
1993	16622.4
1994	16654.4
1995	17045.1
1996	17572
1997	18133.2
1998	18939.5
1999	19972
2000	21068.8
2001	21971
2002	22147.1
2003	21961.7
2004	23020.2
2005	23538.6
2006	24472.1
2007	25366.7
2008	25960.7
2009	25984.2
2010	28321.5
2011	26717.4
2012	29106.2
2013	28601.9
2014	30976
2015	31627.4
2016	30317.8
2017	30742.6
2018	31023.1
2019	31045
2020	29293