| Year | Value | | 2022 | 7.1022312964853 | | 2021 | 2.4778827199272 | | 2020 | 0.3863882245175 | | 2019 | 1.4071993941704 | | 2018 | 2.8962193227031 | | 2017 | 1.5839424857581 | | 2016 | 1.0733938885334 | | 2015 | 0.64824293925449 | | 2014 | 1.4514245236737 | | 2013 | 1.6056305455434 | | 2012 | 2.0490188352116 | | 2011 | 4.8786464170422 | | 2010 | 2.1024424341626 | | 2009 | 5.3110095459529 | | 2008 | 11.006447175638 | | 2007 | 4.3695951420188 | | 2006 | 4.4298114337025 | | 2005 | 3.9514623522091 | | 2004 | 4.9640757674722 | | 2003 | 3.0162412993039 | | 2002 | 1.963567541992 | | 2001 | 4.0554774416642 | | 2000 | 2.3481032742026 |
|