Year	% of relevant age group
1972	18.7827892303467
1973	26.9648094177246
1974	27.8632202148438
1975	29.5715007781982
1976	31.1511096954346
1977	32.3244285583496
1978	33.2122497558594
1979	32.2348594665527
1980	32.4702606201172
1983	34.0461883544922
1985	37.7503890991211
1986	38.645580291748
1987	35.878288269043
1988	35.2836494445801
1989	34.5373497009277
1991	35.4654083251953
1992	35.8322792053223
1993	35.7830200195312
1996	37.7438087463379
1997	40.0939598083496
1999	40.3814086914062
2000	43.6722602844238
2001	46.7644386291504
2002	50.5008697509766
2003	52.7382011413574
2004	57.1328887939453
2005	60.3984909057617
2006	62.097541809082
2007	66.9486465454102
2008	72.2655792236328
2009	72.1639633178711
2010	70.2112731933594
2011	70.9134292602539
2012	72.9042434692383
2013	73.0800170898438
2014	70.790771484375
2015	70.2425689697266
2016	68.9765701293945
2017	67.1826477050781