Year Percent 1950 9.22192 1955 12.10963 1960 10.75848 1965 9.69764 1970 8.22315 1975 8.4762 1980 8.19121 1985 8.19572 1990 7.40285 1995 6.04158 2000 4.8803 2005 4.69063 2010 5.80327 2015 6.01743 2020 5.83144 2025 5.47812 2030 5.10912 2035 4.98833 2040 5.21725 2045 5.52964 2050 5.62654 2055 5.48711 2060 5.28918 2065 5.19842 2070 5.26982 2075 5.4186 2080 5.48979 2085 5.41947 2090 5.26298 2095 5.13984 2100 5.11648