Year Percent 1950 27.08449 1955 28.08389 1960 28.44082 1965 28.501 1970 27.67226 1975 26.49738 1980 26.51026 1985 27.02914 1990 27.37228 1995 27.7795 2000 28.37522 2005 29.63038 2010 31.21484 2015 32.192 2020 32.39973 2025 31.67831 2030 31.12638 2035 31.10532 2040 31.14401 2045 31.24117 2050 30.63282 2055 29.6515 2060 28.89209 2065 28.44595 2070 28.10352 2075 27.62649 2080 26.93629 2085 26.15236 2090 25.45993 2095 24.9352 2100 24.50363