Year % 1998 2.04081632653061 1999 2.04081632653061 2000 2.04081632653061 2002 0 2003 0 2004 0 2005 0 2006 0 2007 0 2008 0 2009 0 2010 0 2011 0 2012 2 2013 2 2014 2 2015 2 2016 2 2017 2 2018 2.04081632653061 2019 4.08163265306122 2020 6.38297872340426 2021 8 2022 8 2023 8