| Year | Value | | 2021 | 11.530031612223 | | 2020 | 11.537407797682 | | 2019 | 11.54478398314 | | 2018 | 11.552160168598 | | 2017 | 11.559536354057 | | 2016 | 11.566912539515 | | 2015 | 11.574288724974 | | 2014 | 11.581594661047 | | 2013 | 11.58890059712 | | 2012 | 11.596206533193 | | 2011 | 11.603512469266 | | 2010 | 11.610818405339 | | 2009 | 11.618124341412 | | 2008 | 11.625430277485 | | 2007 | 11.632736213558 | | 2006 | 11.640042149631 | | 2005 | 11.647348085704 | | 2004 | 11.654654021777 | | 2003 | 11.66195995785 | | 2002 | 11.669265893923 | | 2001 | 11.676571829996 | | 2000 | 11.68387776607 | | 1999 | 11.691218826835 | | 1998 | 11.698559887601 | | 1997 | 11.705900948367 | | 1996 | 11.713242009132 | | 1995 | 11.720583069898 | | 1994 | 11.727924130664 | | 1993 | 11.73526519143 | | 1992 | 11.742606252195 |
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