Year % 1996 20.88 1999 17.61 2000 17.71 2001 11.74 2002 12.51 2003 12.48 2005 13.5 2006 11.35 2007 12.21 2010 12.91 2011 13.03 2012 13.04 2013 12.58 2014 9.52 2015 9.19 2016 10.15 2019 9.24 2020 9.61