Year Percent 1950 26.77421 1955 26.84718 1960 26.01864 1965 24.61778 1970 24.10951 1975 24.97041 1980 26.75597 1985 28.82754 1990 30.2224 1995 30.70941 2000 30.73273 2005 30.73326 2010 30.84113 2015 31.05948 2020 30.94469 2025 30.74046 2030 30.45902 2035 30.01376 2040 29.63418 2045 28.94976 2050 28.0903 2055 27.14945 2060 26.23803 2065 25.36007 2070 24.51721 2075 23.72718 2080 23.01854 2085 22.41814 2090 21.93569 2095 21.55392 2100 21.25947