Year	1=low to 6=high
2009	3.5
2010	3.5
2011	4
2012	4
2013	4.5
2014	4.5
2015	4.5
2016	4.5
2017	4.5
2018	4.5
2019	4.5
2020	4.5
2021	5
2022	5
2023	5