Year Percent 1950 12.63801 1955 13.17753 1960 13.61336 1965 13.67664 1970 13.76177 1975 13.95252 1980 14.62055 1985 14.11283 1990 13.94856 1995 14.54238 2000 15.1782 2005 15.98517 2010 15.37286 2015 15.24621 2020 14.90178 2025 14.84286 2030 14.50878 2035 14.07362 2040 13.57009 2045 13.04222 2050 12.54687 2055 12.07653 2060 11.57009 2065 11.06018 2070 10.55673 2075 10.09794 2080 9.66228 2085 9.25301 2090 8.8539 2095 8.46698 2100 8.085