| Year | Value | | 2017 | 21.25099741 | | 2016 | 17.99032446 | | 2015 | 14.99677482 | | 2014 | 12.2 | | 2013 | 9.6 | | 2012 | 7.1958 | | 2011 | 5 | | 2010 | 3 | | 2009 | 1.95 | | 2008 | 1.75 | | 2007 | 1.406360688 | | 2006 | 1.319573118 | | 2005 | 0.997256559 | | 2004 | 0.754053983 | | 2003 | 0.425182632 | | 2002 | 0.302132016 | | 2001 | 0.175209518 | | 2000 | 0.133282183 | | 1999 | 0.04502077 |
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