| Year | Value | | 2021 | 10.333758073579 | | 2020 | -16.509927749172 | | 2019 | 2.7525599752308 | | 2018 | 8.9558233831382 | | 2017 | -11.028292904357 | | 2016 | -8.3895065143825 | | 2015 | -11.525544599591 | | 2014 | 10.235045780505 | | 2013 | 5.902328993996 | | 2012 | 14.28259402892 | | 2011 | -3.7265268384684 | | 2010 | 11.374100612306 | | 2009 | 42.027335315388 | | 2008 | 0.85050069433008 | | 2003 | -5.5862262294111 | | 2002 | 2.791854729625 | | 2001 | 17.860307192744 | | 2000 | -1.8738637438697 | | 1999 | 2.3144555514284 | | 1998 | 7.0603902160622 | | 1997 | 4.925903375049 | | 1996 | 4.9853593818076 | | 1995 | 0.78947252933484 | | 1994 | -1.647827177599 | | 1993 | -20.285953033099 | | 1992 | 5.0636027237952 | | 1991 | 11.584089161674 | | 1990 | -4.9366917087154 | | 1989 | 0.063017269948148 | | 1988 | 19.93642653166 | | 1987 | -2.3323445480096 | | 1986 | -8.8180686836316 |
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