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	3.5
2012	3.5
2013	3.5
2014	3.5
2015	3
2016	3
2017	2.5
2018	2.5
2019	2.5
2020	2.5
2021	3
2022	3
2023	3