Year % of expense 1992 2.0618556701030926 1993 2.14963707426019 1994 0.7358185981904869 1995 0.8290989960823425 1996 2.3066914358345683 1997 2.3777278710134966 1998 2.796632253964205 1999 2.360128458715247 2000 3.2542384598102414 2001 2.6411708873103312 2002 2.2057170673326603 2003 1.7831999933935379 2004 1.5987247051741809 2005 1.1481868837604112 2006 1.0394307886554024 2007 1.0211656939533444 2008 1.5731504046858338 2009 2.220836306804108 2010 1.7615560832441595 2011 3.2768183835368716 2012 3.9724324860344424 2013 2.870333138083704 2014 3.2833413494527064 2015 5.3355343813654015 2016 6.190155329647183 2017 6.0513629817195165 2018 6.228333926703549 2019 5.616134182066753 2020 5.186469403047882 2021 4.93901783257891 2022 3.226266289015541