Year	% of total primary
1970	15.7379302978516
1971	16.7814903259277
1972	14.8510799407959
1973	14.5219802856445
1974	14.2768697738647
1975	13.9433403015137
1976	13.3883695602417
1977	13.3611698150635
1978	13.3157300949097
1979	13.1725397109985
1980	13.6566200256348
1981	14.4603300094604
1982	14.7431497573853
1983	14.6721200942993
1984	14.3332395553589
1985	14.1229496002197
1986	13.7623195648193
1987	13.3320999145508
1988	12.8644895553589
1989	12.6294603347778
1990	12.4454402923584
1991	12.1655101776123
1992	12.1815795898438
1993	12.0733699798584
1994	11.8873596191406
1995	12.3676996231079
1996	12.2857999801636
1997	12.4383602142334
1998	12.0815601348877
1999	11.8230400085449
2000	11.4722700119019
2001	11.5728902816772
2002	10.9946804046631
2003	10.686619758606
2004	10.5656099319458
2005	10.4671297073364
2006	10.4170598983765
2007	10.6471395492554
2008	10.6951503753662
2009	11.1281900405884
2010	11.4300603866577
2011	12.7897596359253
2012	12.5650997161865
2013	12.0550298690796
2014	11.1956901550293
2015	11.0198497772217
2016	11.1459102630615
2017	12.1049699783325
2018	12.8781700134277
2019	12.5380802154541
2020	12.1534900665283
2021	12.5544700622559
2022	12.6497097015381