Year | Value | 2022 | 6.96 | 2021 | 7.608 | 2020 | 7.507 | 2019 | 6.617 | 2018 | 8.432 | 2017 | 11.208 | 2016 | 13.103 | 2015 | 16.175 | 2014 | 17.29 | 2013 | 17.251 | 2012 | 15.935 | 2011 | 13.678 | 2010 | 11.62 | 2009 | 9.202 | 2008 | 8.53 | 2007 | 9.909 | 2006 | 11.13 | 2005 | 12.598 | 2004 | 13.664 | 2003 | 13.924 | 2002 | 15.053 | 2001 | 20.46 | 2000 | 16.064 | 1999 | 13.559 | 1998 | 11.392 | 1997 | 9.71 | 1996 | 9.68 | 1991 | 11.14 |
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