Year Percent 1950 11.85387 1955 10.3868 1960 10.09532 1965 9.97952 1970 9.20194 1975 7.57695 1980 6.24883 1985 6.04013 1990 6.23841 1995 6.35621 2000 6.09853 2005 6.13238 2010 5.56859 2015 5.25837 2020 5.269 2025 5.29392 2030 5.23785 2035 5.12211 2040 4.97933 2045 4.87455 2050 4.87316 2055 4.94752 2060 4.99394 2065 4.97798 2070 4.90716 2075 4.8333 2080 4.80039 2085 4.81036 2090 4.82273 2095 4.80963 2100 4.76656