Year Percent 1950 13.28429 1955 13.06683 1960 12.69812 1965 14.06098 1970 14.35087 1975 15.71601 1980 15.12886 1985 14.03478 1990 12.97693 1995 12.53901 2000 12.02108 2005 12.39934 2010 11.81977 2015 11.70578 2020 12.4817 2025 11.42182 2030 10.33593 2035 9.83953 2040 9.70095 2045 9.78697 2050 9.65316 2055 9.15104 2060 8.45641 2065 7.88389 2070 7.60814 2075 7.48337 2080 7.30831 2085 6.96205 2090 6.52655 2095 6.13299 2100 5.89152