| Year | Value | | 2021 | 10.873072864971 | | 2020 | 10.682491166878 | | 2019 | 11.191434695633 | | 2018 | 11.576040016932 | | 2017 | 11.639016310875 | | 2016 | 11.43666214929 | | 2015 | 11.550853308059 | | 2014 | 11.795689172535 | | 2013 | 12.035016320271 | | 2012 | 12.209279283991 | | 2011 | 12.147943957498 | | 2010 | 11.943469625849 | | 2009 | 12.221647966104 | | 2008 | 12.568080903009 | | 2007 | 12.244496645018 | | 2006 | 11.697910747497 | | 2005 | 11.258078328618 |
|