| Year | Value | | 2021 | 10.58263964 | | 2020 | 8.565672483 | | 2019 | 7.509161449 | | 2018 | 5.1 | | 2017 | 4 | | 2016 | 3.1 | | 2015 | 2.9 | | 2014 | 2.7 | | 2013 | 2.5 | | 2012 | 2.4 | | 2011 | 2.2 | | 2010 | 2 | | 2009 | 1.8 | | 2008 | 1 | | 2007 | 0.375815961 | | 2006 | 0.311159173 | | 2005 | 0.268195609 | | 2004 | 0.223401395 | | 2003 | 0.151563338 | | 2002 | 0.128537117 | | 2001 | 0.078543428 | | 2000 | 0.053394174 | | 1999 | 0.040894287 | | 1998 | 0.027878201 | | 1997 | 0.014270881 | | 1996 | 0.005849503 |
|