Year	% of tax revenue
1972	30.55119757347558
1973	29.445977917981068
1974	24.864672996716656
1975	25.972074938140686
1976	21.543139490687953
1977	22.508286441069913
1978	21.636876763875822
1979	22.03626220362622
1980	21.173878205128204
1981	20.135311278008814
1982	18.396890666366247
1983	18.40744570837642
1984	16.929448158866382
1985	16.485827637302233
1986	15.803195962994113
1987	15.940681904600954
1988	15.05703422053232
1989	15.375952550771425
1990	4.088799673439732
1991	4.080763274888457
1992	3.9404453292533357
1993	3.9762541481976084
1994	3.7779147902491705
1995	3.6249383364345897
1996	3.8756181615740544
1997	3.070474526483498
1998	2.537803780748278
1999	2.7534948991861152
2000	2.316969753738367
2001	2.458600239977986
2002	2.5280636401296226
2003	2.489544310889583
2004	2.326852966211492
2005	2.0492055579529893
2006	2.018193485018487
2007	1.948030096884437
2008	1.726717357815629
2009	1.8330766647451975
2010	1.8457095091997808
2011	1.765555944003571
2012	1.768738921532797
2013	1.748307854652364
2014	1.7663478903116057
2015	1.6537886022339263
2016	1.7793854903285693
2017	1.6009252103822764
2018	1.604757477612933
2019	1.6090307501103167
2020	1.8231021385051487
2021	1.7019542298800254
2022	1.7172418594354268