Year Percent 1950 27.70165 1955 28.92194 1960 27.11445 1965 25.93847 1970 25.33784 1975 24.57874 1980 25.08251 1985 24.5907 1990 24.29839 1995 24.5165 2000 25.48719 2005 27.60044 2010 28.55477 2015 28.94191 2020 28.2503 2025 27.72904 2030 26.71059 2035 26.0073 2040 25.76256 2045 24.79614 2050 24.18948 2055 23.82931 2060 23.6626 2065 23.72235 2070 23.87457 2075 23.90623 2080 23.64948 2085 23.33779 2090 23.0794 2095 22.90415 2100 22.78294