Year % 2000 22.26 2001 21.94 2002 22.16 2003 22.08 2004 22.11 2005 22.19 2006 22.25 2008 22.55 2009 22.61 2010 23.05 2011 23.19 2012 12.09 2013 11.93 2014 11.85 2015 13.19 2016 13.02 2017 11.89 2018 12.96 2019 12.97 2020 12.98 2021 10.92