Year Percent 1950 12.54 1955 13.72121 1960 15.35421 1965 14.61557 1970 15.62967 1975 14.98091 1980 12.32796 1985 10.80564 1990 9.90383 1995 10.08209 2000 9.50401 2005 8.68572 2010 8.68252 2015 7.98146 2020 7.53422 2025 6.89873 2030 6.55966 2035 6.37609 2040 6.19046 2045 5.94689 2050 5.67968 2055 5.4629 2060 5.30819 2065 5.20771 2070 5.10978 2075 4.99642 2080 4.86625 2085 4.74648 2090 4.66136 2095 4.61041 2100 4.57917