Year Percent 1950 29.58794 1955 32.04566 1960 32.84994 1965 31.49123 1970 25.65379 1975 23.80448 1980 22.67679 1985 23.38339 1990 23.74082 1995 24.90186 2000 27.20472 2005 35.89228 2010 43.31906 2015 48.07259 2020 47.09819 2025 41.04181 2030 32.98602 2035 28.13412 2040 26.69311 2045 26.28068 2050 25.18401 2055 23.08583 2060 21.37903 2065 20.70027 2070 20.90414 2075 21.33316 2080 21.42895 2085 21.09605 2090 20.67069 2095 20.49435 2100 20.6028