Year	1=low to 6=high
2005	3.2857142857142856
2006	3.2
2007	3.246153846153846
2008	3.223076923076923
2009	3.216417910447761
2010	3.1865671641791047
2011	3.152173913043478
2012	3.1338028169014085
2013	3.138888888888889
2014	3.1319444444444446
2015	3.0972222222222223
2016	3.084507042253521
2017	3.0208333333333335
2018	2.992957746478873
2019	2.9452054794520546
2020	2.9383561643835616
2021	2.986111111111111
2022	2.9932432432432434
2023	2.9932432432432434
