Year Percent 1950 19.5371 1955 21.09349 1960 19.64073 1965 19.8334 1970 20.94178 1975 21.22332 1980 23.10555 1985 21.41504 1990 20.51912 1995 22.23509 2000 24.30503 2005 26.80257 2010 27.85184 2015 26.81794 2020 26.8665 2025 28.18707 2030 33.14773 2035 35.5761 2040 34.88598 2045 31.71614 2050 27.13909 2055 25.18228 2060 25.09694 2065 25.6519 2070 25.22582 2075 24.07088 2080 23.42686 2085 23.43371 2090 23.76839 2095 24.09302 2100 24.06994