Year	1=low to 6=high
2005	2.5
2006	2.5
2007	2.5
2008	2.5
2009	2.5
2010	2.5
2011	2.5
2012	3
2013	3
2014	3.5
2015	3.5
2016	3.5
2017	3.5
2018	3.5
2019	4
2020	4
2021	4
2022	4
2023	4