Year % of expense 2001 6.91848398048889 2002 6.0530346822530605 2003 5.527664647964828 2004 6.742360897496361 2006 5.531131336206267 2007 5.035164094676657 2008 6.106631452589424 2009 4.7810375802543215 2010 5.935121981775104 2011 5.782613179067707 2012 5.877651348904868 2013 5.942090195200661 2014 6.618150299555039 2015 6.447040632248088 2016 8.134207129132317 2017 8.745384720797576 2018 10.258910598471754 2019 8.501954039421285 2020 5.149273462089262 2021 5.5303888675512045 2022 6.113015804037288