Year Percent 1950 7.81907 1955 7.75918 1960 8.7683 1965 7.54455 1970 5.76038 1975 6.32943 1980 6.82812 1985 7.76092 1990 5.77131 1995 5.63305 2000 5.43657 2005 4.53434 2010 4.49099 2015 4.58564 2020 4.31492 2025 4.30005 2030 4.28649 2035 4.27258 2040 4.20761 2045 4.19888 2050 4.24672 2055 4.28469 2060 4.3295 2065 4.38607 2070 4.43175 2075 4.46324 2080 4.49204 2085 4.52322 2090 4.5513 2095 4.56582 2100 4.56276