Year % of expense 1994 0.15608099354917254 1995 0.2767877867330012 1996 2.2762807783357926 1997 2.779514974636926 1998 1.9014858610439773 1999 2.2807321664168625 2008 0.44019654035134953 2009 0.9578404167275206 2010 0.44564788176228354 2011 1.7622793254293996 2012 0.742686350874015 2013 1.2690042628686888 2014 0.6455718524538631 2015 1.5682376243499676 2016 3.736947155757856 2017 2.5181083107947724 2018 4.4885220079923 2019 3.1918825218285445 2020 2.3892649400424033 2021 2.4735703865955725