Year % 2000 19.91 2001 12.88 2002 13.2 2003 11.12 2004 11.32 2005 10.04 2006 7.08 2007 6.7 2008 6.11 2009 5.91 2010 7.26 2011 7.18 2012 6.83 2013 6.81 2014 3.65 2015 3.64 2016 4.02 2017 3.64 2020 3.49