| Year | Value | | 2021 | 1,149 | | 2020 | 1,151 | | 2019 | 1,151 | | 2018 | 1,151 | | 2017 | 1,151 | | 2016 | 1,151 | | 2015 | 1,151 | | 2014 | 1,156 | | 2013 | 1,156.9 | | 2012 | 1,156.9 | | 2011 | 1,156.9 | | 2010 | 1,156.9 | | 2009 | 1,157.1 | | 2008 | 1,157.1 | | 2007 | 1,153.6 | | 2006 | 1,154 | | 2005 | 1,075 | | 2004 | 1,075 | | 2003 | 1,111 | | 2002 | 1,120 | | 2001 | 1,121 | | 2000 | 1,139 | | 1999 | 1,140 | | 1998 | 1,219 | | 1997 | 1,322 | | 1996 | 1,326 | | 1995 | 1,326 |
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