Year	% of expense
2008	1.1249687816221412
2009	1.1755772410671
2010	1.2121744518977726
2011	1.3057057948664195
2012	0.9879764691571454
2013	1.2697113861109115
2014	1.364123214211055
2015	1.2060428139901946
2016	0.8875178264531516
2017	0.7559973622274608
2018	0.6829541714842198
2019	0.5886508144078486
2020	0.5995221431209641