| Year | Value | | 2021 | 8,483.0159808519 | | 2020 | 6,828.855865194 | | 2019 | 7,878.6795666081 | | 2018 | 7,834.4872690798 | | 2017 | 7,028.3042228562 | | 2016 | 6,166.8404140064 | | 2015 | 5,880.5134960204 | | 2014 | 6,523.4129000537 | | 2013 | 6,424.3631780798 | | 2012 | 5,887.1443042849 | | 2011 | 6,553.3221679718 | | 2010 | 5,836.8086906417 | | 2009 | 5,857.5271890639 | | 2008 | 6,625.9450827752 | | 2007 | 5,340.972056737 | | 2006 | 4,076.3893575158 |
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