Year Percent 1950 11.14654 1955 12.69717 1960 14.24071 1965 15.25507 1970 16.273 1975 16.18246 1980 16.07301 1985 16.77505 1990 17.38762 1995 18.85992 2000 20.73728 2005 23.41978 2010 24.59672 2015 24.79328 2020 24.0037 2025 22.42084 2030 21.87548 2035 22.59042 2040 24.20117 2045 25.56861 2050 25.8917 2055 25.40695 2060 24.6774 2065 24.29193 2070 24.29643 2075 24.27631 2080 24.03384 2085 23.57012 2090 23.08466 2095 22.74836 2100 22.5718