Year Percent 1950 29.35354 1955 26.86795 1960 25.35208 1965 25.15406 1970 26.59343 1975 27.28776 1980 27.99127 1985 27.57598 1990 26.72267 1995 26.46187 2000 25.84005 2005 25.04439 2010 25.03429 2015 25.77736 2020 25.13669 2025 24.4795 2030 23.72723 2035 22.67477 2040 23.42517 2045 23.94712 2050 23.78848 2055 23.42382 2060 22.93991 2065 22.58737 2070 22.50552 2075 22.58506 2080 22.56876 2085 22.36398 2090 22.04232 2095 21.71045 2100 21.46548