Year Percent 1950 25.97553 1955 26.44517 1960 26.71891 1965 27.26857 1970 27.24643 1975 26.69982 1980 26.19839 1985 25.78986 1990 25.86576 1995 26.68442 2000 27.09156 2005 27.549 2010 27.80001 2015 28.18637 2020 28.75707 2025 29.30389 2030 29.86184 2035 30.30533 2040 30.5922 2045 30.79259 2050 30.85614 2055 30.82461 2060 30.75642 2065 30.61241 2070 30.40189 2075 30.14545 2080 29.85335 2085 29.55807 2090 29.25085 2095 28.93405 2100 28.59547