Year Percent 1950 9.64988 1955 10.88411 1960 11.70661 1965 12.46087 1970 12.41538 1975 9.73173 1980 9.92274 1985 7.95404 1990 7.65779 1995 7.2991 2000 7.16741 2005 6.5357 2010 6.36703 2015 6.11274 2020 5.95338 2025 5.758 2030 5.60489 2035 5.49157 2040 5.42208 2045 5.39591 2050 5.38697 2055 5.37079 2060 5.34884 2065 5.31549 2070 5.28917 2075 5.26258 2080 5.23914 2085 5.20567 2090 5.1647 2095 5.12306 2100 5.08373