Year 1=low to 6=high 2005 3.210526315789474 2006 3.1875 2007 3.225 2008 3.2375 2009 3.2439024390243905 2010 3.2804878048780486 2011 3.402439024390244 2012 3.4069767441860463 2013 3.4204545454545454 2014 3.4651162790697674 2015 3.4651162790697674 2016 3.453488372093023 2017 3.4204545454545454 2018 3.511627906976744 2019 3.4431818181818183 2020 3.4545454545454546 2021 3.441860465116279 2022 3.4204545454545454 2023 3.409090909090909