1993.0 13.0
1994.0 12.6
1995.0 14.6
1996.0 15.3
1997.0 15.4
1998.0 14.4
1999.0 14.1
2000.0 15.6
2001.0 17.1
2002.0 25.8
2003.0 29.4
2004.0 29.9
2005.0 27.1
2006.0 24.2
2007.0 21.5
2008.0 17.5
2009.0 15.1
2010.0 12.6
2011.0 9.8
2012.0 8.9
2013.0 8.0
2014.0 6.7
2015.0 6.8
2016.0 6.4
2017.0 5.5
2018.0 5.6
2019.0 6.3