Year Percent 1950 30.67828 1955 28.02337 1960 25.98551 1965 25.20995 1970 26.35881 1975 29.66127 1980 32.44949 1985 34.80033 1990 34.21942 1995 32.22903 2000 29.88985 2005 28.00337 2010 27.20212 2015 27.76359 2020 27.91418 2025 27.58331 2030 26.89925 2035 25.71589 2040 25.16744 2045 24.94313 2050 24.75609 2055 24.79497 2060 24.56384 2065 24.14169 2070 23.73462 2075 23.48142 2080 23.36335 2085 23.29224 2090 23.17408 2095 22.95922 2100 22.71331