Year 1=low to 6=high 2005 3.1973684210526314 2006 3.1625 2007 3.2125 2008 3.25 2009 3.1951219512195124 2010 3.182926829268293 2011 3.2195121951219514 2012 3.1744186046511627 2013 3.1931818181818183 2014 3.244186046511628 2015 3.244186046511628 2016 3.116279069767442 2017 3.0681818181818183 2018 3.0697674418604652 2019 3.034090909090909 2020 3.0454545454545454 2021 2.9767441860465116 2022 3 2023 2.965909090909091