Year % of total population 1960 40.8899006857948 1961 42.5386699479412 1962 43.8117596505146 1963 44.6933688974878 1964 45.2916800982179 1965 45.6442800266484 1966 45.8211161104736 1967 45.840418223575 1968 45.686599931732 1969 45.3769893630193 1970 44.9153017233832 1971 44.3068007352224 1972 43.5537597702734 1973 42.6650771111866 1974 41.6709620559313 1975 40.5981928308168 1976 39.2554166373271 1977 37.7229875951538 1978 36.2931487689083 1979 35.2555557364117 1980 34.6063435567223 1981 34.0683325392073 1982 33.7162707639198 1983 33.4768754536377 1984 33.3585157168691 1985 33.3725406826737 1986 33.4743423449413 1987 33.6710229037172 1988 33.8956867857451 1989 34.2453596125502 1990 34.5408003084613 1991 34.6464711318928 1992 34.6946844428442 1993 34.6685775790955 1994 34.4932825927579 1995 34.1720082693968 1996 33.7478455898443 1997 33.2280070596957 1998 32.6093503055647 1999 31.8667789017262 2000 30.9937307829946 2001 30.0291486753901 2002 29.0372267405881 2003 28.0641015588926 2004 27.146581108076 2005 26.3062013150865 2006 25.5738399689115 2007 24.9799598148813 2008 24.5116168368354 2009 24.1497350549825 2010 23.9057820806678 2011 23.8098466457125 2012 23.8624834169269 2013 24.0154575206549 2014 24.2115061871268 2015 24.4110496498193 2016 24.5751308507968 2017 24.6239785725498 2018 24.5468674949371 2019 24.4136548590589 2020 24.2241066583594 2021 23.9249531076917 2022 23.4802580093558 2023 22.9217889410781