Year Percent 1950 14.923 1955 15.99155 1960 12.89298 1965 13.66299 1970 14.87986 1975 15.34433 1980 14.67132 1985 15.45727 1990 14.09083 1995 15.34576 2000 13.53424 2005 12.7047 2010 11.8065 2015 10.54728 2020 9.98971 2025 9.44703 2030 8.95118 2035 8.4276 2040 7.87987 2045 7.38187 2050 6.99472 2055 6.72655 2060 6.53337 2065 6.37772 2070 6.22499 2075 6.09685 2080 5.98497 2085 5.92538 2090 5.88722 2095 5.85795 2100 5.82811