Year Percent 1950 27.72155 1955 28.26878 1960 25.19901 1965 25.4196 1970 24.32058 1975 22.63622 1980 23.17919 1985 22.67857 1990 24.39587 1995 26.39776 2000 28.07893 2005 28.00046 2010 26.3687 2015 26.65868 2020 28.52095 2025 29.16334 2030 29.49915 2035 27.8669 2040 24.30808 2045 22.49203 2050 21.84357 2055 21.71876 2060 22.95222 2065 23.6976 2070 23.17695 2075 22.54641 2080 22.13444 2085 22.16575 2090 22.53467 2095 22.88626 2100 22.80507