Year % 2001 11.51539 2002 11.16165 2004 10.21716 2005 9.532641 2006 9.778729 2007 9.205903 2008 11.30137 2009 10.85787 2010 12.46057 2011 13.2454 2012 9.722222 2013 8.041401 2014 14.59684 2015 15.84429 2016 15.5303 2017 5.822058 2018 4.827299 2019 13.37222 2020 13.43608 2021 13.79876