Year	% of total primary
1970	9.42006015777588
1971	9.42245960235596
1972	9.46922969818115
1973	8.96374988555908
1974	8.41345024108887
1975	8.40944004058838
1976	8.19972038269043
1977	7.75139999389648
1978	7.37942981719971
1979	7.14724016189575
1980	7.05810022354126
1981	6.80078983306885
1982	6.86417007446289
1983	6.57541990280151
1984	6.53292989730835
1985	6.50498008728027
1986	6.43727016448975
1987	6.41448020935059
1988	6.26792001724243
1989	6.31581020355225
1990	6.418869972229
1991	6.4624400138855
1992	6.78014993667603
1993	6.60277986526489
1994	6.53267002105713
1995	7.66075992584229
1996	7.69434022903442
1997	7.40828990936279
1998	7.62920999526978
1999	7.79502010345459
2000	8.08761978149414
2001	8.27029037475586
2002	8.24462032318115
2003	8.13181018829346
2004	8.0585298538208
2005	8.15038967132568
2006	8.32063961029053
2007	8.38764953613281
2008	8.62366962432861
2009	9.04710006713867
2010	9.06062984466553
2011	8.67757034301758
2012	8.83145999908447
2013	9.21566963195801
2014	9.24549007415771
2015	9.61565017700195
2016	10.1307401657104
2017	10.7112102508545
2018	10.8277797698975
2019	10.6777801513672
2020	10.4520397186279
2021	10.6752099990845
2022	10.7650499343872