Year % 2000 20.45 2001 20.22 2002 19.87 2003 20.68 2004 19.84 2005 21.09 2006 21.23 2008 20.25 2009 19.91 2010 19.71 2011 20.75 2012 6.45 2013 6.96 2014 7.59 2015 11.13 2016 11.16 2017 12.04 2018 11.39 2019 18.39 2020 11.55 2021 10.55