Year Percent 1950 28.32742 1955 28.83174 1960 28.5791 1965 27.7779 1970 26.77315 1975 25.45796 1980 24.48369 1985 25.96083 1990 28.02032 1995 30.34367 2000 32.07849 2005 33.06514 2010 33.59774 2015 34.15278 2020 34.09867 2025 33.58838 2030 32.54265 2035 31.27254 2040 29.7959 2045 28.19867 2050 26.84027 2055 25.55824 2060 24.29179 2065 23.17778 2070 22.27004 2075 21.58168 2080 21.08002 2085 20.69303 2090 20.40447 2095 20.20222 2100 20.07147