Year Percent 1950 16.95108 1955 18.3849 1960 18.48073 1965 18.61634 1970 18.63249 1975 18.88027 1980 19.09136 1985 18.97944 1990 18.02848 1995 17.24054 2000 16.47146 2005 16.11215 2010 16.28513 2015 16.12636 2020 15.07942 2025 14.14756 2030 13.43478 2035 12.90084 2040 12.41867 2045 11.89218 2050 11.3246 2055 10.74596 2060 10.21585 2065 9.76013 2070 9.35429 2075 8.95377 2080 8.56089 2085 8.17757 2090 7.79435 2095 7.45539 2100 7.13971