Year	1=low to 6=high
2005	3.6
2006	3.5799999999999996
2007	3.66
2008	3.66
2009	3.6799999999999997
2010	3.6799999999999997
2011	3.66
2012	3.66
2013	3.66
2014	3.6
2015	3.56
2016	3.56
2017	3.56
2018	3.5799999999999996
2019	3.6
2020	3.6
2021	3.5799999999999996
2022	3.5799999999999996
2023	3.5799999999999996