Year Percent 1950 14.64753 1955 15.69146 1960 14.36965 1965 14.76069 1970 16.47535 1975 16.75625 1980 16.30482 1985 16.31422 1990 15.78845 1995 15.98721 2000 16.62422 2005 15.49985 2010 13.85278 2015 13.3781 2020 13.10592 2025 12.67181 2030 11.99504 2035 11.24611 2040 10.58406 2045 10.05764 2050 9.62086 2055 9.19588 2060 8.75095 2065 8.29077 2070 7.87664 2075 7.50328 2080 7.18057 2085 6.87963 2090 6.5934 2095 6.32904 2100 6.08071