Year Percent 1950 19.65131 1955 18.53142 1960 18.64284 1965 19.53335 1970 17.74879 1975 14.41661 1980 14.09009 1985 14.96202 1990 13.77377 1995 13.87253 2000 13.38022 2005 13.19238 2010 12.80468 2015 11.8886 2020 10.86017 2025 10.62689 2030 10.68069 2035 10.58777 2040 10.17027 2045 9.4565 2050 8.74767 2055 8.30892 2060 8.16077 2065 8.04615 2070 7.76 2075 7.29908 2080 6.81004 2085 6.44304 2090 6.2459 2095 6.13387 2100 5.98949