Year Percent 1950 17.75497 1955 17.79309 1960 17.44737 1965 16.87675 1970 15.95376 1975 15.73509 1980 16.14695 1985 17.09453 1990 17.81468 1995 18.68726 2000 20.03122 2005 21.64449 2010 24.70976 2015 26.56787 2020 26.30218 2025 25.15628 2030 24.51387 2035 24.40302 2040 24.99248 2045 25.59937 2050 25.41984 2055 24.90965 2060 24.68254 2065 24.6466 2070 24.69166 2075 24.41165 2080 24.04757 2085 23.68175 2090 23.36746 2095 23.12685 2100 22.95339