Year Percent 1950 17.62253 1955 16.71403 1960 17.19845 1965 17.43178 1970 17.59934 1975 20.09915 1980 19.38884 1985 17.86596 1990 16.94828 1995 16.30363 2000 15.59921 2005 15.21673 2010 14.84449 2015 13.85865 2020 12.74846 2025 12.01826 2030 11.52968 2035 11.08674 2040 10.5495 2045 9.95528 2050 9.35561 2055 8.84353 2060 8.4025 2065 8.02709 2070 7.65259 2075 7.27558 2080 6.90725 2085 6.57483 2090 6.28546 2095 6.05429 2100 5.84852