| Year | Value | | 2022 | 182.1773224818 | | 2021 | 148.16437814868 | | 2020 | 142.80130331753 | | 2019 | 135.86657466717 | | 2018 | 131.49749312117 | | 2017 | 128.868078299 | | 2016 | 127.81300924995 | | 2015 | 125.80402926316 | | 2014 | 124.21733384394 | | 2013 | 119.29149793391 | | 2012 | 112.14618539853 | | 2011 | 107.5689885611 | | 2010 | 100 | | 2009 | 94.35515989606 | | 2008 | 94.222129861591 | | 2007 | 87.543596222776 | | 2006 | 83.644129733866 | | 2005 | 78.50547947321 | | 2004 | 73.256355671217 | | 2003 | 66.317990603374 | | 2002 | 57.423467120287 | | 2001 | 51.905241964766 | | 2000 | 48.144301586966 | | 1999 | 38.489378901588 | | 1998 | 17.085726128253 | | 1997 | 8.9463087297325 | | 1996 | 7.016225035574 | | 1995 | 6.2077074164435 | | 1994 | 5.1906547331004 | | 1993 | 4.8608699455989 | | 1992 | 4.5741949729403 | | 1991 | 4.1634866018027 | | 1990 | 3.6701599122932 | | 1989 | 2.7057499266819 | | 1988 | 1.6771253827207 |
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