Year % of relevant age group 1975 100.03838 1976 99.93453 1977 98.86789 1978 96.94329 1981 94.89552 1998 105.01609 1999 97.98383 2000 93.96577 2001 95.69106 2005 95.11003 2015 93.7864 2016 96.76357 2017 96.12859 2018 96.75865