Year Percent 1950 27.79792 1955 25.97105 1960 27.62487 1965 26.08302 1970 25.35694 1975 26.01704 1980 25.8806 1985 27.57714 1990 29.80466 1995 29.33969 2000 27.29902 2005 25.16535 2010 23.303 2015 23.18339 2020 23.45189 2025 22.47952 2030 20.94551 2035 20.09099 2040 19.82197 2045 20.11801 2050 20.58624 2055 20.78169 2060 20.63649 2065 20.30639 2070 20.09487 2075 20.14294 2080 20.35991 2085 20.53768 2090 20.50062 2095 20.25365 2100 19.95453