Year Percent 1950 12.94534 1955 13.16455 1960 11.9144 1965 14.76457 1970 13.28368 1975 11.79775 1980 9.58167 1985 9.59268 1990 9.5503 1995 8.98223 2000 9.54531 2005 7.79173 2010 5.51151 2015 5.75099 2020 4.97224 2025 4.61516 2030 4.47984 2035 4.36461 2040 4.26886 2045 3.94924 2050 3.66615 2055 3.52946 2060 3.50061 2065 3.50708 2070 3.48211 2075 3.42498 2080 3.36387 2085 3.34585 2090 3.39924 2095 3.49277 2100 3.59474