Year	% of expense
1990	31.83963266867905
1991	33.43247262403678
1992	32.518740629685155
1993	32.76375798114928
1994	33.85665734307799
1995	35.62162296755559
1996	38.22338396931845
2017	18.625770757365242
2018	17.258583663599133
2019	18.571937685420888
2020	20.311662879258506
2021	17.179965258221692
2022	7.097722048683204