Year % of total population 1960 36.62756537638188 1961 36.702299856177696 1962 36.71570461735761 1963 36.66759527273005 1964 36.545825750244475 1965 36.4149637630573 1966 36.300037315038786 1967 36.163314683626005 1968 36.00687408465221 1969 35.83080593436552 1970 35.6292220969263 1971 35.40636384936484 1972 35.1692974481874 1973 34.93180569699752 1974 34.721585924350855 1975 34.54122964278135 1976 34.3857157014339 1977 34.2361459290815 1978 34.09359585624834 1979 33.971709527917085 1980 33.87849176711031 1981 33.81727500223901 1982 33.7838293618485 1983 33.784909320195034 1984 33.80042912741704 1985 33.82608876015332 1986 33.867148187347695 1987 33.92003157031964 1988 33.970285163527656 1989 34.044826282536114 1990 34.124524569161025 1991 34.11188267505631 1992 33.98626079081507 1993 33.84769149054429 1994 33.75862790477701 1995 33.57919187476019 1996 33.27410949810575 1997 32.89837878957365 1998 32.466893415495235 1999 31.978638021847445 2000 31.515013047215927 2001 31.11479443812032 2002 30.72666522886418 2003 30.30361056380687 2004 29.805972999112857 2005 29.27784120795811 2006 28.760456710149754 2007 28.25222488268443 2008 27.761125979236585 2009 27.30146839763505 2010 26.96451739134243 2011 26.73804525360681 2012 26.485286115789687 2013 26.240271133153303 2014 26.025401618185512 2015 25.769730541566048 2016 25.491779293526445 2017 25.202850722598917 2018 24.91681920157896 2019 24.658767349503055 2020 24.440174782548056 2021 24.230754451676184 2022 23.980654948708896 2023 23.709481298903064