Year	1=low to 6=high
2005	3.2435897435897427
2006	3.222500000000001
2007	3.2425000000000006
2008	3.251219512195122
2009	3.2780487804878056
2010	3.314634146341464
2011	3.3119047619047626
2012	3.3357142857142854
2013	3.3232558139534887
2014	3.3536585365853653
2015	3.3512195121951227
2016	3.323684210526317
2017	3.328947368421053
2018	3.33421052631579
2019	3.338461538461538
2020	3.3578947368421055
2021	3.3631578947368426
2022	3.3923076923076927
2023	3.3974358974358974