Year Percent 1950 29.7824 1955 27.85242 1960 27.1582 1965 26.0692 1970 26.80047 1975 27.41246 1980 28.65521 1985 30.49503 1990 30.62338 1995 30.34051 2000 29.15264 2005 27.97698 2010 27.12847 2015 26.84597 2020 26.26756 2025 25.13152 2030 24.45782 2035 24.18582 2040 24.3053 2045 24.60481 2050 24.22436 2055 23.65055 2060 23.2005 2065 22.97219 2070 22.95246 2075 22.95702 2080 22.8003 2085 22.47589 2090 22.12507 2095 21.86046 2100 21.7071