Year Percent 1950 11.0703 1955 10.56192 1960 10.22631 1965 11.09313 1970 12.11259 1975 12.17067 1980 10.81749 1985 10.23397 1990 12.6149 1995 14.26495 2000 15.92953 2005 17.00602 2010 17.73426 2015 19.35198 2020 21.26676 2025 23.0963 2030 24.19879 2035 25.67573 2040 26.75768 2045 28.30405 2050 30.32921 2055 31.06306 2060 29.64106 2065 29.0786 2070 29.94841 2075 30.75184 2080 31.38215 2085 31.85246 2090 31.99017 2095 31.96357 2100 32.16809