Year Percent 1950 20.06526 1955 21.87452 1960 20.46512 1965 20.81849 1970 22.00693 1975 22.25869 1980 24.12685 1985 22.18734 1990 21.11046 1995 22.78985 2000 24.80688 2005 27.42998 2010 28.44609 2015 27.35662 2020 27.05228 2025 27.74601 2030 32.14272 2035 34.21313 2040 33.43645 2045 30.37633 2050 25.84642 2055 23.76595 2060 23.53663 2065 24.05257 2070 23.63495 2075 22.62039 2080 22.10078 2085 22.22691 2090 22.65595 2095 23.04446 2100 23.07925