| Year | Value | | 2022 | 11.98151173447 | | 2021 | 4.085102853351 | | 2020 | 1.5755329008342 | | 2019 | 1.8492298451109 | | 2018 | 1.959840762938 | | 2017 | 3.1310624859011 | | 2016 | 1.1223139741777 | | 2015 | 1.3923582200019 | | 2014 | 2.0824479388015 | | 2013 | 7.6942636289666 | | 2012 | 7.3303858959665 | | 2011 | 11.137397634213 | | 2010 | 6.1425536024725 | | 2009 | 8.1169509223808 | | 2008 | 12.410986775178 | | 2007 | 6.3917064439141 | | 2006 | 11.724022998083 | | 2005 | 16.119980648283 | | 2004 | 11.026362718346 | | 2003 | 9.8761788972958 | | 2002 | 19.490832157969 | | 2001 | 95.005225810001 | | 2000 | 71.120628794654 | | 1999 | 42.453905464297 | | 1998 | 30.159699799284 | | 1997 | 23.307866135801 | | 1996 | 95.600926120817 | | 1995 | 82.660515186466 |
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