Year	% of tax revenue
1972	0.4590395480225989
1973	0.6358860934476085
1974	0.41274936941068563
1975	0.3676470588235294
1976	0.5688674366488536
1977	0.755891507336594
1978	0.7324595219737857
1979	0.5550811272416738
1980	0.20172678124747842
1981	0.17925001792500178
1982	0.19516233958247087
1983	0.20791101408597124
1984	0.17144051850303157
1985	0.19063545150501673
1986	0.1423487544483986
1987	0.04856230031948882
2004	0.00027889724031180714
2005	0.000236967947715392
2009	0.005846069204019575
2010	0.010228942550774578
2011	0.008439454394631458
2012	0.006650810010369021
2013	0.010131342723403415
2014	0.01159193571746218
2015	0.011453824155063035
2016	0.009943126088400502
2017	0.006905213686219548
2018	0.005841778518966959
2019	0.0067685423029082755
2020	0.003941401196079451
2021	0.03583963578117173
2022	0.057487653503810215