Year Percent 1950 16.94866 1955 16.74801 1960 16.6138 1965 14.76141 1970 15.19167 1975 14.59463 1980 16.63546 1985 19.04868 1990 24.0498 1995 26.14718 2000 28.04425 2005 29.18297 2010 28.8267 2015 27.68124 2020 25.51197 2025 23.30768 2030 20.98814 2035 20.43436 2040 20.29436 2045 20.66456 2050 22.49656 2055 22.93782 2060 23.26093 2065 23.28049 2070 22.25281 2075 21.70767 2080 21.45086 2085 21.26962 2090 20.87615 2095 20.34074 2100 19.84574