Year Percent 1950 12.40636 1955 12.44628 1960 12.5608 1965 12.80479 1970 13.10502 1975 13.41872 1980 13.64198 1985 13.73564 1990 13.73811 1995 13.36193 2000 12.79182 2005 11.99995 2010 11.32298 2015 11.36362 2020 12.49006 2025 14.67799 2030 16.83984 2035 17.98996 2040 18.45978 2045 19.14317 2050 20.27546 2055 21.61945 2060 22.7385 2065 23.14136 2070 23.17664 2075 23.44039 2080 23.89031 2085 24.34808 2090 24.63106 2095 24.6826 2100 24.60513