Year Percent 1950 11.34748 1955 11.04938 1960 10.93591 1965 11.4433 1970 10.22855 1975 9.81095 1980 8.81656 1985 7.5491 1990 6.09183 1995 5.72627 2000 5.49175 2005 5.5955 2010 4.95082 2015 4.6118 2020 4.1206 2025 3.887 2030 3.95188 2035 4.06219 2040 4.10586 2045 4.04684 2050 3.93399 2055 3.85849 2060 3.90837 2065 4.0472 2070 4.19247 2075 4.26091 2080 4.25152 2085 4.21093 2090 4.20494 2095 4.25856 2100 4.33873