| Year | Value | | 2021 | 13.195220895938 | | 2020 | -7.8363832058223 | | 2019 | -5.0945316015579 | | 2018 | -5.6068474214014 | | 2017 | 5.7443749939014 | | 2016 | -1.9274140206198 | | 2015 | 5.2659875518724 | | 2014 | -3.5939320300429 | | 2013 | 2.1475342599263 | | 2012 | -1.3794773194871 | | 2011 | 8.8193965555438 | | 2010 | 11.57898269602 | | 2009 | -7.5044207950061 | | 2008 | 5.6591942401675 | | 2007 | 12.053024144932 | | 2006 | 20.744797536093 | | 2005 | 7.3245207342618 | | 2004 | 0.8519991005772 | | 2003 | 11.641210299395 | | 2002 | -11.040879786076 | | 2001 | -4.7183428857914 | | 2000 | 0.94947227426935 | | 1999 | -5.6470420984424 | | 1998 | 3.0854265894626 | | 1997 | 7.3972920390321 | | 1996 | 6.8187534042799 | | 1995 | -4.6678175095981 | | 1994 | 4.861248402895 | | 1993 | 5.3098683729495 | | 1992 | 14.233317673406 | | 1991 | 15.47297471618 | | 1990 | 0.34479977592177 | | 1989 | -12.584178702352 | | 1988 | -3.0676481323295 | | 1987 | -1.1775465864425 | | 1986 | 13.762256063337 | | 1985 | 33.222022506355 | | 1984 | -24.770800493782 |
|