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