Year Percent 1950 20.06453 1955 19.997 1960 20.11848 1965 20.70035 1970 20.99547 1975 20.6584 1980 20.37303 1985 20.55094 1990 22.08814 1995 24.53945 2000 27.58769 2005 29.85123 2010 29.41489 2015 28.04429 2020 26.47748 2025 25.30936 2030 25.21712 2035 25.64811 2040 25.3848 2045 24.46014 2050 24.03967 2055 23.47825 2060 23.48697 2065 23.74593 2070 23.54621 2075 23.21309 2080 22.87858 2085 22.65022 2090 22.53295 2095 22.48919 2100 22.39247