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