Year	1=low to 6=high
2005	3.5
2006	3.5
2007	3.5
2008	3.5
2009	3.5
2010	3.5
2011	4
2012	4
2013	4
2014	4
2015	4
2016	4
2017	4.5
2018	4.5
2019	4.5
2020	4.5
2021	4
2022	4
2023	4