Year Number 1996 1.41046285629272 1998 1.11060059070587 2000 0.822056412696838 2002 1.35895538330078 2003 0.962002456188202 2004 1.08964920043945 2005 1.10395002365112 2006 1.07445085048676 2007 1.284419298172 2008 1.33927059173584 2009 1.19087398052216 2010 1.15264821052551 2011 1.19352161884308 2012 1.34056687355042 2013 1.36410057544708 2014 1.27070045471191 2015 1.12933051586151 2016 0.8921759724617 2017 1.02962338924408 2018 0.884671747684479 2019 0.892080426216125 2020 0.887528836727142 2021 0.899418652057648 2022 0.637995362281799