Year Percent 1950 11.03696 1955 10.88472 1960 10.78432 1965 10.42383 1970 9.8388 1975 9.36745 1980 7.93969 1985 7.80907 1990 7.6122 1995 7.436 2000 6.97329 2005 6.46133 2010 6.76556 2015 6.68672 2020 6.72838 2025 6.39091 2030 6.07545 2035 5.86515 2040 5.83371 2045 5.88229 2050 5.89806 2055 5.81755 2060 5.68672 2065 5.56361 2070 5.48453 2075 5.45382 2080 5.42745 2085 5.37864 2090 5.29593 2095 5.20104 2100 5.12036