Year % of relevant age group 1975 102.72301 1976 102.50657 1977 100.51764 1978 99.90603 1981 96.24176 1998 109.48866 1999 103.5008 2000 98.27118 2001 99.6207 2005 96.75403 2015 99.0364 2016 96.14325 2017 95.36261 2018 97.08458