Year	% of total primary
1970	3.51624989509583
1971	3.5689799785614
1972	3.60283994674683
1973	3.77694010734558
1974	3.75453996658325
1975	3.68527007102966
1980	2.59984993934631
1981	2.67314004898071
1982	2.8740599155426
1983	3.06049990653992
1984	3.11500000953674
1985	3.45489001274109
1986	3.47281002998352
1987	3.99384999275208
1988	4.38454008102417
1989	4.47497987747192
1990	4.65780019760132
1991	4.72273015975952
1992	4.88845014572144
1993	4.81030988693237
1994	4.86408996582031
1995	4.98089981079102
1996	5.43073987960815
1997	5.56853008270264
1998	6.77502012252808
1999	6.65936994552612
2000	6.89381980895996
2001	6.82053995132446
2002	6.98448991775513
2004	6.85829019546509
2005	6.10788011550903
2006	7.03184986114502
2007	7.51496982574463
2008	7.79594993591309
2009	8.10717010498047
2010	8.10262966156006
2011	8.45291996002197
2012	8.46094989776611
2013	8.88059997558594
2014	8.75537014007568
2015	8.97692966461182
2016	9.05233001708984
2017	9.06352996826172
2018	8.91001987457275
2019	8.75821018218994
2020	8.97696971893311
2021	8.53182983398438
2022	9.25831031799316