Year % of total population 1960 9.579313225293745 1961 9.734232051817944 1962 9.893997139195262 1963 10.0375075249181 1964 10.201691067673472 1965 10.40158489248187 1966 10.61877523976531 1967 10.835749225337118 1968 11.036763399794063 1969 11.225455350484804 1970 11.425658437946266 1971 11.62630675591987 1972 11.824712206040008 1973 12.022754489947285 1974 12.21537457619367 1975 12.399691107519486 1976 12.564537188263962 1977 12.739482771580342 1978 12.919796040160495 1979 13.072874610702964 1980 13.113570876835187 1981 13.005047973059012 1982 12.830136402818788 1983 12.633554055524607 1984 12.528170911800451 1985 12.612573504721654 1986 12.80135907323665 1987 13.001267006222283 1988 13.20393592749489 1989 13.40009059186109 1990 13.597566383225079 1991 13.79948983258519 1992 14.000568289689443 1993 14.209986127190833 1994 14.429778831285212 1995 14.66935706263707 1996 14.903018157931406 1997 15.111516797067988 1998 15.304682012139194 1999 15.502172227496038 2000 15.725602012040149 2001 15.960476050421633 2002 16.185367136212246 2003 16.38603401902456 2004 16.60249022674241 2005 16.842621977451017 2006 17.054486668421998 2007 17.202608952616096 2008 17.339717980533827 2009 17.509592005153866 2010 17.66255783837032 2011 17.86231476236804 2012 18.170562754795746 2013 18.51489761432512 2014 18.880792700129 2015 19.223579277285612 2016 19.541093628719967 2017 19.84737019338527 2018 20.148755745916038 2019 20.459726345631044 2020 20.762261349572302 2021 21.04050556559909 2022 21.251323715433138 2023 21.533176426029073