Year Percent 1950 32.98766 1955 31.90772 1960 30.59057 1965 29.39912 1970 28.69316 1975 28.66632 1980 28.33228 1985 28.02189 1990 27.66807 1995 27.64289 2000 28.67149 2005 29.14963 2010 29.60031 2015 29.5589 2020 28.48113 2025 28.01415 2030 27.51619 2035 27.07679 2040 26.76474 2045 26.2363 2050 25.65471 2055 24.99177 2060 24.39183 2065 23.87323 2070 23.41589 2075 22.98946 2080 22.57649 2085 22.1851 2090 21.82314 2095 21.51576 2100 21.25433