Year 1=low to 6=high 2005 3.95 2006 4 2007 4.1875 2008 4.3125 2009 4.388888888888889 2010 4.333333333333333 2011 4.1875 2012 4.3125 2013 4.3125 2014 4 2015 4 2016 4.1 2017 4.2 2018 4.1 2019 4.2 2020 4.125 2021 4.125 2022 4.125 2023 4.125