Year Percent 1950 10.05804 1955 11.67141 1960 11.82073 1965 12.07642 1970 11.31247 1975 9.82992 1980 9.36444 1985 8.76884 1990 8.45405 1995 8.1906 2000 8.35477 2005 7.34521 2010 6.72318 2015 7.22395 2020 6.66392 2025 6.37491 2030 6.1062 2035 5.81226 2040 5.58011 2045 5.45975 2050 5.39236 2055 5.3023 2060 5.17692 2065 5.05945 2070 4.96348 2075 4.90087 2080 4.87026 2085 4.84349 2090 4.80466 2095 4.75262 2100 4.70842