Year Percent 1950 12.22768 1955 12.37725 1960 15.25536 1965 16.10141 1970 16.48464 1975 15.60061 1980 14.41667 1985 14.0168 1990 14.00687 1995 12.66823 2000 11.7609 2005 10.31094 2010 9.7672 2015 9.36222 2020 9.57075 2025 8.79684 2030 8.04187 2035 7.3974 2040 6.93776 2045 6.64677 2050 6.42538 2055 6.17448 2060 5.87776 2065 5.58734 2070 5.36097 2075 5.21672 2080 5.1284 2085 5.05289 2090 4.95843 2095 4.85764 2100 4.77008