| Year | Value | | 2022 | 86.027158928387 | | 2021 | 86.872188185009 | | 2020 | 87.385643984113 | | 2019 | 86.295986815445 | | 2018 | 84.662132556057 | | 2017 | 85.137836035386 | | 2016 | 85.685219402034 | | 2015 | 83.284558685908 | | 2014 | 81.232149522974 | | 2013 | 82.9126669873 | | 2012 | 83.579856964243 | | 2011 | 82.972651175833 | | 2010 | 82.477153693336 | | 2009 | 83.544778928138 | | 2008 | 85.691154374539 | | 2007 | 83.855184127261 | | 2006 | 83.487789748409 | | 2005 | 84.414881542885 | | 2004 | 84.093488957304 | | 2003 | 85.833201870244 | | 2002 | 83.889860729098 | | 2001 | 82.390553938037 | | 2000 | 83.306157101082 | | 1999 | 81.964775126926 | | 1998 | 81.131164998393 | | 1997 | 81.096366296929 | | 1996 | 83.386638420113 | | 1995 | 83.106546825354 | | 1994 | 82.373702008171 | | 1993 | 84.615393711635 | | 1992 | 84.860837535804 | | 1991 | 84.987572415599 |
|