Year	1=low to 6=high
2005	3.1
2006	3
2007	3.1
2008	3.1
2009	3.1
2010	3.1
2011	3.1
2012	3.1
2013	3.1
2014	3.1
2015	3.1
2016	3.2
2017	3.2
2018	3.2
2019	3.1
2020	3
2021	3
2022	3
2023	3