Year Percent 1950 29.27149 1955 29.9507 1960 27.38756 1965 26.08336 1970 24.00229 1975 22.69146 1980 25.48767 1985 25.5201 1990 25.03763 1995 25.6104 2000 25.84852 2005 27.89278 2010 30.2181 2015 29.74931 2020 28.12373 2025 26.31511 2030 25.11118 2035 25.22202 2040 25.3569 2045 24.60057 2050 23.27518 2055 22.62114 2060 22.51623 2065 22.87843 2070 23.26373 2075 23.29069 2080 22.97812 2085 22.52775 2090 22.22147 2095 22.15176 2100 22.20833