Year % of expense 2011 1.2724822398010043 2012 0.9325945319292801 2014 2.8780346037413604 2015 2.639690673893853 2016 3.2715742056179797 2017 6.089578442409937 2018 9.962579500192408 2019 8.085825657449721 2020 8.133083461538702 2021 9.649041750160027