Year Percent 1950 8.27924 1955 8.94799 1960 8.14437 1965 8.02122 1970 8.49255 1975 8.16709 1980 7.54631 1985 6.25103 1990 5.29342 1995 4.91727 2000 4.78122 2005 4.61292 2010 4.67653 2015 4.72289 2020 4.34386 2025 4.16695 2030 4.09538 2035 4.1438 2040 4.25257 2045 4.35083 2050 4.38934 2055 4.38187 2060 4.39123 2065 4.45332 2070 4.54681 2075 4.62311 2080 4.65437 2085 4.63904 2090 4.59666 2095 4.56603 2100 4.55645