Year Percent 1950 26.77953 1955 28.38465 1960 28.07823 1965 25.26279 1970 25.21593 1975 25.63283 1980 26.5453 1985 26.38947 1990 26.10878 1995 30.00643 2000 27.33279 2005 28.10224 2010 30.67029 2015 30.74914 2020 31.11595 2025 31.10547 2030 31.14804 2035 32.32175 2040 32.59039 2045 32.27026 2050 31.54377 2055 30.98594 2060 30.64692 2065 30.33365 2070 29.79407 2075 28.95294 2080 27.96667 2085 27.0384 2090 26.27309 2095 25.60602 2100 24.95189