Year Percent 1950 14.62688 1955 13.92609 1960 14.0495 1965 15.72275 1970 14.49521 1975 12.91947 1980 12.10549 1985 10.01681 1990 9.19554 1995 7.28175 2000 7.80686 2005 6.79631 2010 5.30525 2015 4.66599 2020 4.48618 2025 4.50329 2030 4.51986 2035 4.57156 2040 4.41099 2045 4.08373 2050 3.95709 2055 4.06316 2060 4.27133 2065 4.47634 2070 4.59221 2075 4.55705 2080 4.43714 2085 4.40239 2090 4.49284 2095 4.63286 2100 4.73228