Year	% of expense
2007	26.29898791927836
2008	26.707532476705303
2009	26.231989033158044
2010	24.849114087991765
2011	25.596442747698074
2012	25.426845752173357
2013	15.722324948073457
2014	15.054474360093895
2015	14.4724624721455
2016	14.705600848874717
2017	15.088913638988805
2018	16.050941137082127
2019	16.627613435844836
2020	15.64561088154661
2021	16.499614926433434
2022	16.745825122467046