Year % 2000 18.07 2001 17.15 2004 16.37 2005 16.87 2006 15.78 2007 15.41 2008 14.23 2014 8.12 2015 7.92 2016 9.27 2017 9.88 2018 9.83 2019 9.52 2020 9.52 2021 8.84