Year	1=low to 6=high
2005	3.481818181818182
2006	3.4654761904761906
2007	3.506289308176101
2008	3.5075471698113203
2009	3.5185185185185186
2010	3.5061728395061724
2011	3.481818181818183
2012	3.452380952380953
2013	3.4415204678362583
2014	3.4006407692307685
2015	3.3557687820512823
2016	3.3469383673469393
2017	3.3367346938775517
2018	3.312925170068028
2019	3.3133333200000004
2020	3.2916666666666665
2021	3.2847222499999997
2022	3.2925170000000006
2023	3.309523775510205
