Year	% of total primary
1970	14.5019302368164
1971	13.7592000961304
1972	13.099889755249
1973	13.2284698486328
1974	12.8339796066284
1975	12.9056100845337
1976	12.9994697570801
1977	13.0293998718262
1980	13.1260595321655
1981	13.3705997467041
1982	12.9131803512573
1983	12.9092702865601
1984	12.2722396850586
1985	14.3877897262573
1986	12.1173000335693
1987	12.0817499160767
1988	12.22815990448
1989	12.355019569397
1990	12.5688600540161
1991	12.189920425415
1992	12.38623046875
1993	12.3230495452881
1994	12.3271799087524
1995	12.0775804519653
1996	11.734169960022
1997	12.0620498657227
1999	12.6436595916748
2000	13.0081701278687
2001	13.473349571228
2002	13.7414102554321
2003	14.391489982605
2005	16.3995990753174
2006	17.5564002990723
2007	18.959810256958
2008	20.0800590515137
2009	21.0921497344971
2010	22.0650405883789
2011	23.526050567627
2013	26.1259803771973
2014	27.1693000793457
2015	27.3728408813477
2016	27.2221603393555
2017	27.2275199890137
2018	25.9467906951904
2019	26.0632305145264
2020	24.0827102661133
2021	22.1776695251465
2022	25.5570106506348