Year Percent 1950 13.5877 1955 12.32344 1960 12.90661 1965 13.47927 1970 13.8754 1975 14.20142 1980 14.61358 1985 14.86076 1990 15.04742 1995 14.5774 2000 13.95824 2005 14.46756 2010 14.74438 2015 14.34324 2020 13.6659 2025 13.17683 2030 12.76465 2035 12.37068 2040 11.92438 2045 11.44406 2050 10.94246 2055 10.4687 2060 10.03336 2065 9.61454 2070 9.23096 2075 8.84226 2080 8.46247 2085 8.10441 2090 7.76076 2095 7.44268 2100 7.13122