Year % 1997 8.75 1998 8.75 1999 5 2000 5 2001 5 2002 5 2003 5 2004 18 2005 18 2006 18 2007 18 2008 6 2009 10 2010 10 2011 10 2012 10 2013 12.1212121212121 2014 24 2015 24 2016 24 2018 20 2019 21 2020 21 2021 23 2022 31 2023 31