Year % 1997 9.375 1998 9.375 1999 9.375 2001 18.75 2002 18.75 2003 18.75 2004 19.3548387096774 2005 12.9032258064516 2006 12.9032258064516 2007 16.1290322580645 2008 18.75 2009 14.2857142857143 2010 12.5 2011 12.5 2012 12.5 2013 12.5 2014 12.9032258064516 2015 21.875 2016 21.875 2017 25 2018 25 2019 25 2020 34.375 2021 34.375 2022 34.375 2023 37.5