Year % 2000 2.65233145627231 2001 2.58579755403255 2002 2.26733067497949 2003 2.18631717848106 2004 1.86794475200406 2005 1.76025084535995 2006 1.66180499911901 2007 1.34034365230322 2008 1.32499491422633 2009 1.21429941736426 2010 0.952984526022005 2011 0.91104690238738 2012 0.829668811257567 2013 0.792144846890663 2014 0.578464749726835 2015 0.563038905428015 2016 0.510467470041659 2017 0.506977666032018 2018 0.50619085970671 2019 0.470863923975913 2020 0.345089245036867