Year | Value | 2021 | 22.001004742313 | 2020 | 21.860419276163 | 2019 | 22.285170990077 | 2018 | 20.870103903181 | 2017 | 20.780653358752 | 2016 | 21.277375275638 | 2015 | 20.931220827141 | 2014 | 21.599174552522 | 2013 | 21.586213875292 | 2012 | 17.491642076611 | 2011 | 17.219419049099 | 2010 | 17.07005139901 | 2009 | 16.505863232784 | 2008 | 17.321758732108 | 2007 | 15.962531729107 | 2006 | 14.395986559394 | 2005 | 14.335663408846 | 2004 | 13.996405646619 |
|