Year Percent 1950 28.57218 1955 27.47019 1960 26.60305 1965 24.23316 1970 23.03871 1975 22.5808 1980 21.64468 1985 21.54395 1990 22.78528 1995 23.43014 2000 25.34983 2005 28.25716 2010 31.79378 2015 34.97004 2020 36.2099 2025 35.65634 2030 34.47136 2035 33.69628 2040 33.63522 2045 33.61105 2050 33.01659 2055 32.09051 2060 31.11109 2065 30.33668 2070 29.70403 2075 29.04997 2080 28.28355 2085 27.47946 2090 26.74775 2095 26.14223 2100 25.64734