Year 1=low to 6=high 2005 3.205555555555556 2006 3.177083333333334 2007 3.1875000000000004 2008 3.178125 2009 3.1868686868686864 2010 3.146464646464646 2011 3.1414141414141414 2012 3.1176470588235294 2013 3.132352941176471 2014 3.1565658585858585 2015 3.1464649494949493 2016 3.1010102020202024 2017 3.0588235294117645 2018 3.085858585858585 2019 3.009803911764705 2020 3.0098039215686265 2021 3.04040403030303 2022 3.044117617647058 2023 3.068627411764705