Year Percent 1950 15.2682 1955 16.10712 1960 19.20023 1965 20.01128 1970 19.49963 1975 18.76438 1980 18.3036 1985 20.16099 1990 19.16161 1995 15.36763 2000 11.61212 2005 9.67477 2010 9.7008 2015 10.17327 2020 9.21848 2025 7.66731 2030 6.2913 2035 5.61565 2040 5.58505 2045 5.70704 2050 5.55624 2055 5.11633 2060 4.6657 2065 4.43213 2070 4.45652 2075 4.58163 2080 4.63565 2085 4.5519 2090 4.40577 2095 4.31364 2100 4.32754