Year Percent 1950 30.01783 1955 29.9673 1960 28.34038 1965 24.35836 1970 23.84059 1975 25.68902 1980 27.24692 1985 29.50069 1990 30.74711 1995 29.15661 2000 28.41207 2005 29.02176 2010 29.95112 2015 30.82004 2020 31.69002 2025 30.67894 2030 30.52227 2035 30.94832 2040 31.05991 2045 31.81302 2050 31.01621 2055 29.98321 2060 29.30045 2065 29.23499 2070 29.54065 2075 29.82077 2080 29.65417 2085 29.04412 2090 28.40907 2095 28.04581 2100 27.95756