Year Percent 1950 10.70606 1955 12.0186 1960 12.65333 1965 13.00937 1970 13.42071 1975 13.65164 1980 12.87889 1985 11.90604 1990 11.7787 1995 11.67532 2000 11.23135 2005 9.62991 2010 8.04177 2015 7.26452 2020 7.43041 2025 8.48589 2030 8.00539 2035 7.22997 2040 6.44544 2045 5.98081 2050 5.95393 2055 6.10387 2060 6.113 2065 5.88063 2070 5.53733 2075 5.29564 2080 5.23435 2085 5.27894 2090 5.30498 2095 5.24217 2100 5.11065