Year	% of relevant age group
1970	61.67929
1971	61.61668
1972	62.24654
1973	64.1709
1974	61.53408
1975	69.25453
1976	73.15239
1977	74.10039
1978	74.07878
1979	82.07804
1980	77.51301
1981	76.1002
1982	77.55333
1983	79.90005
1984	81.41886
1985	81.19014
1986	85.52171
1987	84.66611
1988	84.31293
1989	84.04824
1990	85.02866
1991	87.04233
1992	86.92158
1993	86.17153
1994	85.89847
1995	85.43711
1996	87.02335
1997	87.83682
1998	89.81541
1999	92.96993
2000	94.06039
2001	95.0395
2002	98.00765
2003	98.26383
2004	98.94792
2005	100.2249
2006	100.8831
2007	102.5099
2008	102.3771
2009	103.04
2010	103.9147
2011	104.3749
2012	104.9816
2013	104.3841
2014	104.1777
2015	103.0912
2016	102.6462
2017	101.9699
2018	101.0914