Year Percent 1950 9.35028 1955 9.91037 1960 10.36024 1965 11.41511 1970 12.65799 1975 13.52654 1980 13.9625 1985 14.91079 1990 18.99986 1995 20.47161 2000 21.69428 2005 22.47625 2010 24.67276 2015 27.00349 2020 29.3497 2025 31.98766 2030 34.46388 2035 37.44541 2040 39.91155 2045 41.25394 2050 41.66935 2055 41.86421 2060 42.22622 2065 42.58846 2070 42.77478 2075 42.6644 2080 42.25282 2085 41.82256 2090 41.59899 2095 41.5305 2100 41.53345