Year Percent 1950 10.0822 1955 7.88109 1960 6.97694 1965 7.5712 1970 8.01553 1975 8.86376 1980 8.50717 1985 6.01027 1990 5.38655 1995 5.87013 2000 6.05285 2005 5.39561 2010 5.12486 2015 4.71999 2020 4.47321 2025 4.55722 2030 4.73685 2035 4.82749 2040 4.72987 2045 4.56557 2050 4.47248 2055 4.50149 2060 4.63429 2065 4.76592 2070 4.81395 2075 4.7764 2080 4.71263 2085 4.67587 2090 4.6962 2095 4.73417 2100 4.75833