Year 1=low to 6=high 2005 3.700000000000001 2006 3.6783333333333337 2007 3.7631944444444447 2008 3.775 2009 3.741666666666667 2010 3.734615384615385 2011 3.6442307692307705 2012 3.5779761904761913 2013 3.5547619047619046 2014 3.384091818181818 2015 3.3613630303030306 2016 3.360605454545455 2017 3.3613636363636386 2018 3.3636363636363655 2019 3.4143938181818188 2020 3.375 2021 3.3991665000000006 2022 3.3924999 2023 3.4091665