| Year | Value | | 2021 | 1,328.11 | | 2020 | 1,321.36 | | 2019 | 1,315.92 | | 2018 | 1,315.59 | | 2017 | 1,311.58 | | 2016 | 1,306.51 | | 2015 | 1,312.7 | | 2014 | 1,309.9 | | 2013 | 1,308.8 | | 2012 | 1,314.2 | | 2011 | 1,312.7 | | 2010 | 1,310.4 | | 2009 | 1,307 | | 2008 | 1,310 | | 2007 | 1,310 | | 2006 | 1,290 | | 2005 | 1,290 | | 2004 | 1,280 | | 2003 | 1,280 | | 2002 | 1,280 | | 2001 | 1,280 | | 2000 | 1,280 |
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