Year Percent 1950 30.9154 1955 28.3092 1960 25.57974 1965 24.18465 1970 23.28821 1975 24.52109 1980 27.23992 1985 31.6705 1990 34.67419 1995 34.94698 2000 33.49392 2005 30.10979 2010 26.28117 2015 24.27713 2020 24.17732 2025 25.64772 2030 26.69728 2035 27.01082 2040 26.23056 2045 25.03901 2050 24.35088 2055 23.80533 2060 23.51903 2065 23.14672 2070 22.56804 2075 21.88642 2080 21.28842 2085 20.87373 2090 20.61807 2095 20.44204 2100 20.2701