Year Percent 1950 22.52354 1955 23.2988 1960 20.94039 1965 21.52447 1970 21.59655 1975 21.1703 1980 21.73865 1985 20.68475 1990 21.19928 1995 23.40716 2000 26.07288 2005 27.75878 2010 28.06851 2015 27.89158 2020 28.76208 2025 29.74519 2030 30.91835 2035 30.58534 2040 28.0867 2045 25.4484 2050 23.65537 2055 22.77629 2060 23.26993 2065 24.11432 2070 24.15513 2075 23.69624 2080 23.11628 2085 22.78296 2090 22.86413 2095 23.19305 2100 23.37462