Year 1=low to 6=high 2005 3.2945205479452064 2006 3.2600000000000007 2007 3.2808219178082196 2008 3.291891891891892 2009 3.2973684210526324 2010 3.3315789473684214 2011 3.328571428571428 2012 3.315189873417722 2013 3.3 2014 3.2880000000000003 2015 3.2840000000000007 2016 3.2527777777777778 2017 3.2328767123287663 2018 3.262499999999999 2019 3.267567567567567 2020 3.2777777777777772 2021 3.2845070422535207 2022 3.2931506849315073 2023 3.298630136986301