Year	1=low to 6=high
2005	3.5
2006	4
2007	4
2008	4
2009	4
2010	3.5
2011	3.5
2012	3.5
2013	3.5
2014	3.5
2015	3.5
2016	3
2017	3
2018	3
2019	3
2020	3
2021	3
2022	3
2023	3