| Year | Value | | 2021 | 1.7715349013026 | | 2020 | -8.4413871336969 | | 2019 | -1.0461185898714 | | 2018 | 1.2308848741501 | | 2017 | 3.7306564417647 | | 2016 | 3.6970938868294 | | 2015 | 5.072015732851 | | 2014 | 1.0616750320945 | | 2013 | 6.9701819018515 | | 2012 | 0.77753436518712 | | 2011 | 1.5468639541446 | | 2010 | -8.6625251296221 | | 2009 | 8.4317774674133 | | 2008 | 0.010211500547257 | | 2007 | 7.6030988729033 | | 2006 | 0.9067326534216 | | 2005 | 3.1275729811344 | | 2004 | 4.3773369446368 | | 2003 | -5.1498316871456 | | 2002 | -1.6115276049764 | | 2001 | -2.3506871270775 | | 2000 | 58.861088196029 | | 1999 | -15.669859196137 | | 1998 | 1.5249879673797 | | 1997 | 5.0376601514426 | | 1996 | 15.468889422857 | | 1995 | 20.883320866276 | | 1994 | -3.7763281775129 | | 1993 | -3.0443356778287 | | 1992 | -3.0493245477315 | | 1991 | 1.2212005262918 | | 1990 | 0.0046833225628973 | | 1989 | -5.0285334218008 |
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