Year	1=low to 6=high
2005	2.5
2006	2.5
2007	2.5
2008	2.5
2009	2.5
2010	3
2011	3.5
2012	3.5
2013	4
2014	4
2015	3.5
2016	3
2017	2
2018	2
2019	2
2020	2
2021	2
2022	2
2023	2