Year Percent 1950 12.57107 1955 12.47128 1960 14.08552 1965 13.93649 1970 13.74409 1975 13.4915 1980 13.57885 1985 13.36236 1990 13.05967 1995 11.95302 2000 10.83292 2005 10.19834 2010 9.81188 2015 9.48187 2020 9.33746 2025 8.83208 2030 8.30432 2035 7.82159 2040 7.44099 2045 7.15646 2050 6.90222 2055 6.62977 2060 6.35705 2065 6.10406 2070 5.906 2075 5.75136 2080 5.61685 2085 5.49902 2090 5.38296 2095 5.28014 2100 5.19936