| Year | Value | | 2021 | 35.752351600372 | | 2020 | 35.800507239398 | | 2019 | 35.848662878423 | | 2018 | 35.896818517448 | | 2017 | 35.944974156474 | | 2016 | 35.993129795499 | | 2015 | 36.041285434524 | | 2014 | 36.08944107355 | | 2013 | 36.137596712575 | | 2012 | 36.1857523516 | | 2011 | 36.233907990626 | | 2010 | 36.282063629651 | | 2009 | 36.330219268676 | | 2008 | 36.378374907702 | | 2007 | 36.426530546727 | | 2006 | 36.474686185752 | | 2005 | 36.522841824778 | | 2004 | 36.570997463803 | | 2003 | 36.619153102828 | | 2002 | 36.667308741854 | | 2001 | 36.715464380879 | | 2000 | 36.763620019904 | | 1999 | 36.81177565893 | | 1998 | 36.859931297955 | | 1997 | 36.90808693698 | | 1996 | 36.956242576006 | | 1995 | 37.004398215031 | | 1994 | 37.052553854056 | | 1993 | 37.100709493082 | | 1992 | 37.148865132107 | | 1991 | 37.197020771132 | | 1990 | 37.245176410158 |
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