Year % of expense 2002 7.348714693430766 2003 9.172780424542205 2004 8.632371025988546 2005 8.209938974045295 2006 6.674298383824931 2007 5.4254376882293815 2008 5.735164159464276 2009 5.8656956885573335 2010 0.7422202909690615 2011 0.8564238050244942 2012 0.8205298584742837 2013 1.200443441663694 2014 1.0991284502115988 2015 0.5669557442929954 2016 2.6222429330266483 2017 0.6383127774592264 2018 1.932307120317038 2019 3.2849764924881777 2020 3.568940156383061 2021 6.766550484228609