Year Percent 1950 11.6771 1955 12.76044 1960 13.86786 1965 14.77689 1970 12.94888 1975 12.62828 1980 10.42866 1985 8.90296 1990 8.95064 1995 9.42148 2000 8.9274 2005 6.6711 2010 6.66089 2015 6.04202 2020 6.1641 2025 6.15742 2030 5.98594 2035 5.82725 2040 5.66152 2045 5.54142 2050 5.49454 2055 5.48067 2060 5.42947 2065 5.33128 2070 5.2202 2075 5.1323 2080 5.0716 2085 5.03273 2090 4.99448 2095 4.94777 2100 4.89595