Year Percent 1950 12.28169 1955 12.83078 1960 16.31438 1965 16.05391 1970 15.79345 1975 15.62277 1980 16.06582 1985 16.16295 1990 15.80237 1995 14.71268 2000 13.10013 2005 13.21915 2010 11.89467 2015 13.02791 2020 11.28148 2025 9.60384 2030 9.15984 2035 8.58305 2040 8.1902 2045 7.76077 2050 7.17695 2055 6.60852 2060 6.16616 2065 5.87071 2070 5.66046 2075 5.46702 2080 5.26221 2085 5.0615 2090 4.89498 2095 4.79138 2100 4.73284