Year % 2002 27.92 2003 25.36 2004 25.4 2005 25.43 2006 29.04 2007 28.14 2008 27.26 2009 27.13 2012 19.32 2015 8.95 2016 8.63 2017 16.16 2020 19.1 2021 17.26