Year Percent 1950 26.21675 1955 25.21319 1960 24.93351 1965 25.1997 1970 25.81525 1975 27.49492 1980 29.01535 1985 30.34557 1990 31.10381 1995 30.85823 2000 30.66903 2005 30.52893 2010 30.96119 2015 31.51232 2020 31.95077 2025 32.21801 2030 32.11734 2035 31.68531 2040 31.28165 2045 31.02127 2050 30.79154 2055 30.4002 2060 29.9129 2065 29.39681 2070 28.88157 2075 28.3511 2080 27.79597 2085 27.22156 2090 26.62819 2095 26.04908 2100 25.51323