Year % 1999 8.98 2000 9.27 2001 8.88 2002 7.68 2003 7.4 2004 7.41 2005 5.73 2006 5.96 2007 6.13 2008 5.85 2009 6.83 2010 7.6 2011 6.11 2012 6.11 2013 3.82 2014 3.04 2015 2.88 2016 2.95 2017 5 2018 3.43 2019 3.34 2020 2.9 2021 2.92