Year Percent 1950 13.1752 1955 13.46652 1960 13.98243 1965 14.84529 1970 15.29157 1975 14.28403 1980 13.50132 1985 12.94192 1990 12.45784 1995 11.59063 2000 9.59794 2005 8.00577 2010 7.22303 2015 7.33898 2020 8.28903 2025 7.7314 2030 6.92278 2035 6.14455 2040 5.69202 2045 5.65873 2050 5.79131 2055 5.79393 2060 5.57965 2065 5.27223 2070 5.06771 2075 5.03527 2080 5.09957 2085 5.13646 2090 5.07544 2095 4.93983 2100 4.81938