| Year | Value | | 2022 | 187.86468635854 | | 2021 | 173.51210526893 | | 2020 | 163.61696683362 | | 2019 | 155.85819507068 | | 2018 | 148.1723703599 | | 2017 | 141.45090212616 | | 2016 | 135.42749430984 | | 2015 | 127.04684307242 | | 2014 | 123.08540678397 | | 2013 | 116.81225062533 | | 2012 | 111.39285564625 | | 2011 | 105.03663052102 | | 2010 | 100 | | 2009 | 102.46452023524 | | 2008 | 123.24289088446 | | 2007 | 111.31477160483 | | 2006 | 103.05736544382 | | 2005 | 97.157277207831 | | 2004 | 93.928136611202 | | 2003 | 89.435419259371 | | 2002 | 83.875195362877 | | 2001 | 62.681099493454 | | 2000 | 69.349891543079 | | 1999 | 65.34307054029 | | 1996 | 104.47680507966 | | 1995 | 95.560691905013 | | 1994 | 87.453064088477 | | 1993 | 80.814374457802 | | 1992 | 71.431389456643 | | 1991 | 60.943854036657 | | 1990 | 51.788611389895 | | 1989 | 46.391117590684 | | 1988 | 40.435655023201 | | 1987 | 36.279357055454 | | 1986 | 32.464672619303 | | 1985 | 27.511276411167 | | 1984 | 24.277334978728 | | 1983 | 21.874653139839 | | 1982 | 18.617937471961 | | 1981 | 16.602417635547 | | 1980 | 14.76909168265 | | 1979 | 12.70188071392 | | 1978 | 10.949561846493 | | 1977 | 9.6485869954363 | | 1976 | 8.2686833460996 | | 1975 | 7.4216802306237 | | 1974 | 6.4981649478081 | | 1973 | 5.7291505502426 |
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