Year years 2003 3.8 2004 3.8 2005 3.8 2006 3.8 2007 2.5 2008 2.5 2009 2.5 2010 2.5 2011 2.5 2012 2.5 2013 2.5 2014 2.5 2015 2.5 2016 2.5 2017 2.5 2018 2.5 2019 2.5