Year % 2000 18.79 2001 18.24 2002 17.15 2003 18.54 2004 17.03 2005 19.64 2006 19.76 2008 18.39 2009 17.74 2010 17.94 2011 18.36 2012 1.91 2013 1.92 2014 2.05 2015 5.52 2016 5.27 2017 4.82 2018 4.63 2019 28.04 2020 5.06 2021 7.89