| Year | Value | | 2022 | 54.238658933636 | | 2021 | 53.82406995142 | | 2020 | 53.450927769061 | | 2019 | 53.569561000595 | | 2018 | 53.00000374068 | | 2017 | 52.250637105004 | | 2016 | 51.747749298661 | | 2015 | 51.282951338851 | | 2014 | 50.820892349941 | | 2013 | 50.227622997119 | | 2012 | 49.563610082373 | | 2011 | 48.807899415696 | | 2010 | 47.891582455925 | | 2009 | 46.892887159133 | | 2008 | 45.96415713273 | | 2007 | 44.896102846144 | | 2006 | 43.815837863268 | | 2005 | 42.813022631095 | | 2004 | 41.867721558642 | | 2003 | 40.879451684153 | | 2002 | 39.973262778037 | | 2001 | 39.153816221145 | | 2000 | 38.37438208659 | | 1999 | 37.650691937288 | | 1998 | 36.951225251741 | | 1997 | 36.213691739547 | | 1996 | 35.425457026772 | | 1995 | 34.544509833866 | | 1994 | 33.636150304555 | | 1993 | 32.777572616262 | | 1992 | 32.008781441538 | | 1991 | 31.433378163356 |
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