Year Number 1996 1.45976829528809 1998 1.46096003055573 2000 1.4913969039917 2002 1.46941840648651 2003 1.22844505310059 2004 1.14331793785095 2005 0.847438395023346 2006 1.06922149658203 2007 1.09091985225677 2008 1.11797952651978 2009 0.890962958335876 2010 0.894479393959045 2011 0.876532793045044 2012 0.890999794006348 2013 0.895805478096008 2014 0.586509823799133 2015 0.783619344234467 2016 0.764758408069611 2017 0.744137227535248 2018 0.739916861057281 2019 0.733900785446167 2020 0.727434754371643 2021 0.741474807262421 2022 0.72119528055191