| Year | Value | | 2023 | 0.47169810533524 | | 2022 | 0.47169810533524 | | 2021 | 0.47619047760963 | | 2019 | 0.47619047760963 | | 2018 | 0.47619047760963 | | 2017 | 1.4285714626312 | | 2016 | 1.4285714626312 | | 2015 | 1.9047619104385 | | 2014 | 6.25 | | 2013 | 10.426540374756 | | 2012 | 8.0568723678589 | | 2011 | 11.374407768249 | | 2010 | 14.354066848755 | | 2009 | 13.397129058838 | | 2008 | 19.417476654053 | | 2007 | 18.932039260864 | | 2006 | 19.512195587158 | | 2005 | 19.607843399048 | | 2004 | 14.925373077393 | | 2003 | 21.621622085571 | | 2002 | 19.45945930481 | | 2000 | 23.497268676758 | | 1998 | 24.043716430664 | | 1996 | 31.693988800049 |
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