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