Year	% of tax revenue
1972	5.900855561147458
1973	6.062035617407713
1974	5.541284403669724
1975	5.938426775879114
1976	5.508274231678487
1977	5.831435079726652
1978	5.2803433156078
1979	5.805682157004728
1980	5.5972050367566775
1981	5.5015290519877675
1982	5.4266220594821
1983	4.950037684471567
1984	5.186851365195314
1985	5.525664986502048
1986	5.577838205302515
1987	4.86993937023274
1988	4.837957721151413
1989	4.499178588130898
1990	4.356974464053583
1991	3.5789382878462748
1992	3.7761117152177643
1993	3.7528588650165053
1994	3.4554783148919763
1995	3.3111257255597173
1996	2.700133105153071
1997	2.640558138041218
1998	2.776738610943572
1999	2.590796251919241
2000	2.489922988694085
2001	2.619352270465467
2002	2.9270921635443976
2003	2.855678819399964
2004	2.6820855576705642
2005	2.421766213131141
2006	2.0357854180951445
2007	2.1558935651695608
2008	2.125640406077861
2009	2.2593256582499945
2010	2.1520110520818125
2011	2.0215965340095114
2012	2.243858995332268
2013	2.422453044963005
2014	2.6497630061104447
2015	3.0635768188228143
2016	3.8033191717504855
2017	3.6528881386635925
2018	3.6700895885476363
2019	3.4977415172528774
2020	4.357392399860614
2021	3.767642307860221
2022	3.0775014574770845