Year % 2001 13.02 2002 6.55 2004 7.24 2005 7.27 2006 6.71 2007 5.88 2008 5.98 2009 6.1 2010 5.51 2011 5.42 2012 5.71 2013 5.58 2014 5.66 2015 5.62 2016 5.35 2017 5.36 2018 5.23 2019 5.15 2020 5.14 2021 4.89